There are over 1403 POP locations worldwide with DDOS protection, failover systems, unlimited traffic and HTTPS access.
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This kind of database load-balancing software, for example, transparently enables failover, scale out and faster throughput.
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On top of that, though, Google then implemented a modular multi-process architecture and some failover and recovery services.
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Given those locations, it can be hard to provide backup generators and other failover infrastructure, and servicing them can also be challenging.
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It secures your website against DDos attacks, and provides load balancing and failover directly from the cloud, with real-time health and monitoring notifications.
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In the event of a region failure, we transparently handle the failover and ensure continuity for your users and applications accessing data in Cloud Storage.
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Granted, that nightmare scenario is why companies implement disaster recovery or failover systems, but the easier (and simpler) solution is to build an infrastructure that flat-out works, regardless of circumstances.
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For example, a customer might control costs by creating a rule to find the cloud with lowest cost for processing a given job, or provide failover control across regions and clouds — all automatically.
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"Salesforce chose Azure because it is a trusted platform with a global footprint, multi-layered security approach, robust disaster recovery strategy with auto failover, automatic updates and more," a Salesforce spokesperson told TechCrunch.
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Because you're actually renting a physical machine, any hardware issue on that machine will impact the virtual machines you are running on them, so chances are you'll want to have multiple dedicated hosts for your failover strategy anyway.
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" The final outcome, according to Elon, is pretty dramatic: He says that whereas Tesla's computer vision software running on Nvidia's hardware was handling about 200 frames per second, its specialized chip is able to crunch out 2,000 frames per second "with full redundancy and failover.
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The commercial product has always been on the drawing board, but they are releasing it now because large enterprise customers are demanding additional features such as replication and failover hardware nodes for high availability, which is essential for companies using the product for mission critical purposes.
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So developers have been using legacy database software from folks like Oracle and PostgreSQL for their systems of record and then new database software like Microsoft Azure's CosmosDB, Amazon's DynamoDB, Apache's Cassandra (which the fellas used at Facebook) or MongoDB for distributed transactions for applications (things like linear write/read scalability, plus auto-rebalancing, sharding and failover).
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Fault Tolerant Messaging or Failover Abstraction is the ability to transparently “failover” a call or request from one service transport protocol to another upon failure with no changes to the functional code or business logic implementation. In elemenope, this ability to “failover” is achieved via Dispatcher Failover [DFo] configuration. The elemenope framework has the ability to configure multiple nested failover chains. A typical use of the DFo functionality is the failover from a synchronous service transport protocol to an asynchronous service transport protocol.
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CUBRID High Availability provides load-balanced, fault-tolerant and continuous service availability through its shared-nothing clustering, automated fail-over and manual fail-back mechanisms. CUBRID's 3-tier architecture allows native support for High-Availability with two-level auto failover: the broker failover and server failover.
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In computing and related technologies such as networking, failover is switching to a redundant or standby computer server, system, hardware component or network upon the failure or abnormal termination of the previously active application, For application-level failover, see for example . server, system, hardware component, or network. Failover and switchover are essentially the same operation, except that failover is automatic and usually operates without warning, while switchover requires human intervention. Systems designers usually provide failover capability in servers, systems or networks requiring near-continuous availability and a high degree of reliability.
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Scout also features application failover support in a disaster recovery. The 6.2 release of the Scout supported on Microsoft Windows, Linux, Solaris, AIX and HP UX. It also supports VMware, XenServer, Hyper-V, Solaris Zones and a few other server virtualization platforms. Both server and application failover is supported for the Microsoft Windows. Application Failover supports Microsoft Exchange, BlackBerry Enterprise Server, Microsoft SQL Server, File Servers, Microsoft Sharepoint, Oracle, MySQL among others.
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Some systems have the ability to send a notification of failover. Certain systems, intentionally, do not failover entirely automatically, but require human intervention. This "automated with manual approval" configuration runs automatically once a human has approved the failover. Failback is the process of restoring a system, component, or service previously in a state of failure back to its original, working state, and having the standby system go from functioning back to standby.
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In this instance, the wireless failover allows business transactions to continue to be processed, ensuring business continuity.
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Wireless failover is an automated function in telephone networks and computer networks where a standard hardwired connection is switched to a redundant wireless connection upon failure or irregular closure of a default hardwired connection or component in the network such as a router, server, or computer. Wireless failover is a business continuity function. That is, it allows businesses to continue operations even in the event of a network failure. In retail, wireless failover is typically used when a standard connection for a point of sale credit card machine fails.
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Windows Server 2008 offers high availability to services and applications through Failover Clustering. Most server features and roles can be kept running with little to no downtime. In Windows Server 2008, the way clusters are qualified changed significantly with the introduction of the cluster validation wizard. The cluster validation wizard is a feature that is integrated into failover clustering in Windows Server 2008.
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Cluster Shared Volumes (CSV) is a feature of Failover Clustering first introduced in Windows Server 2008 R2 for use with the Hyper-V role. A Cluster Shared Volume is a shared disk containing an NTFS or ReFS (ReFS: Windows Server 2012 R2 or newer) volume that is made accessible for read and write operations by all nodes within a Windows Server Failover Cluster.
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Performance testing has shown that Fuse Message Broker exhibits the highest performance of any open source messaging platform, and has clustering and failover to ensure high availability.
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It is self-contained, eliminating the need for an external database. WS_FTP's additional built-in capabilities include email client integration, alerts and notification, server failover, and transfer scheduling.
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The current version uses HTML5 and responsive design to deliver cross-platform availability. The applications runs in two geographically dispersed datacentres with automated failover to achieve 99.999% uptime.
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If the computer systems in a server room are mission critical, removing single points of failure and common-mode failures may be of high importance. The level of desired redundancy is determined by factors such as whether the organisation can tolerate interruption whilst failover systems are activated, or must they be seamless without any business impacts. Other than computer hardware redundancy, the main consideration here is the provisioning of failover power supplies and cooling.
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When the master unit fails, an automatic failover to the hot spare occurs within a very short time and the outputs from the hot spare, now the master unit, are delivered to the controlled devices and displays. The controlled devices and displays may experience a short blip or disturbance during the failover time. However, they can be designed to tolerate/ignore the disturbances so that the overall system operation is not affected.
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N+1 redundancy is a form of resilience that ensures system availability in the event of component failure. Components () have at least one independent backup component (+1). The level of resilience is referred to as active/passive or standby as backup components do not actively participate within the system during normal operation. The level of transparency (disruption to system availability) during failover is dependent on a specific solution, though degradation to system resilience will occur during failover.
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Migration is similar to the failover capability some virtualization suites provide. In true failover, the host may have suddenly completely failed, which precludes the latest state of the VM having been copied to the backup host. However, the backup host has everything except for the very latest changes, and may indeed be able to resume operation from its last known coherent state. Because the operations are so similar, systems that provide one capability may provide the other.
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SD-WAN applies similar technology to a wide area network (WAN). SDN technology is currently available for industrial control applications that require extremely fast failover. One company boasts 100x Faster Failover for Mission-critical processes (fails over in less than 100 μs, compared to 10 ms for traditional networks) along with the elimination of certain Cyber Vulnerabilities that are associated with traditional network management switches. Research of SDN continues as many emulators are being developed for research purposes, like vSDNEmul, EstiNet, Mininet etc.
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Switchover is the manual switch from one system to a redundant or standby computer server, system, or network upon the failure or abnormal termination of the previously active server, system, or network, or to perform system maintenance, such as installing patches, and upgrading software or hardware. Automatic switchover of a redundant system on an error condition, without human intervention, is called failover. Manual switchover on error would be used if automatic failover is not available, possibly because the overall system is too complex.
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1 in 2005.GnuGk Paper at Fostel 2004 In 2006, version 2.2.4 introduced call failover, ENUM and CLI rewriting.GnuGk Paper at Fostel 2006 In 2012, version 3.0 added IPv6 and full H.460.18/H.
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Wireless failover solutions are offered in different forms. A radio may be installed into the network. Examples of this may include a 3G or 4G network connection. Additionally, 3G or 4G network cards may be used.
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MessagePlus/Open can be deployed in virtualized environments like VMware and supports, as standard, high availability cluster solutions including AIX High Availability Cluster Multi-Processing (HACMP), SUN Solaris Cluster and Microsoft Cluster Server / Failover Clustering (MSCS).
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A simple form of high availability is implemented: when used in the client-server mode, the database engine supports hot failover (this is commonly known as clustering). However, the clustering mode must be enabled manually after a failure.
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Active and passive replication is also available, maintaining an identical copy of a master database for application failover. The subsystem implements an asynchronous single master multi-slave replication engine based on its supporting client–server transports (including TCP/IP).
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Mearian, Lucas. "Nimbus puts up its new all-flash array against disk arrays", 31 January 2012. Retrieved on 28 November 2012. Nimbus Data software detects controller and path failures, providing failover as well as online software updates and online capacity expansion.
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StorTrends iTX 2.8 is designed to support Storage Bridge Bay specification that provide Auto- Failover capability to ensure that any interruption is handled without affecting data. It supports High-availability cluster, redundancy, scalability, replication, disaster recovery and multiple site backups.
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Cluster management algorithms are provided like failover mechanisms or automatic cluster installation. In-database analytics is supported. Exasol integrates support to run Lua, Java, Python and GNU R scripts in parallel inside user defined functions (UDFs) within the DBMS' SQL pipeline.
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Similar to replication, the primary purpose of log shipping is to increase database availability by maintaining a backup server that can replace a production server quickly. Other databases such as Adaptive Server Enterprise and Oracle Database support the technique but require the Database Administrator to write code or scripts to perform the work. Although the actual failover mechanism in log shipping is manual, this implementation is often chosen due to its low cost in human and server resources, and ease of implementation. In comparison, SQL server clusters enable automatic failover, but at the expense of much higher storage costs.
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Cloud Spanner Booth at Google Cloud Summit Spanner is a NewSQL database developed by Google. Spanner is a globally distributed database service and storage solution. It provides features such as global transactions, strongly consistent reads, and automatic multi-site replication and failover.
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The use of virtualization software has allowed failover practices to become less reliant on physical hardware through the process referred to as migration in which a running virtual machine is moved from one physical host to another, with little or no disruption in service.
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Ipswitch Analytics was released in 2015 to monitor and report data through the MOVEit software. The analytic data includes an activity monitor and automated report creation. Ipswitch Analytics can access data from MOVEit file transfer and automation servers. That same year, Ipswitch Failover was released.
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If the information in the PU-side cache is not outdated, a PE identity may be directly selected from cache, skipping the effort of asking a PR for handle resolution. After re-establishing a connection with a new PE, the state of the application session has to be re-instantiated on the new PE. The procedure necessary for session resumption is denoted as Failover Procedure and is of course application-specific. For an FTP download for example, the failover procedure could mean to tell the new FTP server the file name and the last received data position. By that, the FTP server will be able to resume the download session.
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Trapeze Networks, Inc. was founded in 2002. It is a Wi-Fi networking infrastructure and services vendor. In Sept 2007 Trapeze was recognized by Frost and Sullivan as the first company to apply controller virtualization techniques to wireless networks resulting in session-level hitless failover capabilities.
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Normally, two System Service Processors were used per platform. One was configured as Main and the other as Spare. Only the SSP in the role of Main could control the platform at any given time. Failover between Main and Spare was performed automatically by the SSP software.
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The gateway may be audited to determine the controlling call agent, a query that may be used to resolve any conflicts. In case of multiple call agents, MGCP assumes that they maintain knowledge of device state among themselves. Such failover features take into account both planned and unplanned outages.
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XtreemFS has been under development since early 2007. A first public release was made in August 2008. XtreemFS 1.0 was released in August 2009. The 1.0 release includes support for read-only replication with failover, data center replica maps, parallel reads and writes, and a native Windows client.
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In many cases, peer networks do not want to track such movements as it would require, potentially, maintaining context involving multiple certificates and device lifecycles. Where privacy is also a consideration, the details of device maintenance, failover, load balancing and replacement cannot be inferred by tracking authentication events.
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That software was integrated with Egenera PAN Manager and PAN Domain Manager and became PAN Cloud Director. The three products combined are the Egenera Cloud Suite. Egenera has received numerous patents for its technology, including the Processing Area Network, N+1 disaster recovery and virtualized server failover technology.
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Compared to database replication, log shipping does not provide as much in terms of reporting capabilities, but backs up system tables along with data tables, and locks the standby server from users' modifications. A replicated server can be modified (e.g. views) and is therefore unsuitable for failover purposes.
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MPLS and its predecessors, as well as ATM, have been called "fast packet" technologies. MPLS, indeed, has been called "ATM without cells".Interview with the author (of an MPLS-based VPN article) , G. Pildush Virtual circuits are especially useful in building robust failover mechanisms and allocating bandwidth for delay-sensitive applications.
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Parallel Redundancy Protocol (PRP) is a network protocol standard for Ethernet that provides seamless failover against failure of any network component. This redundancy is invisible to the application. PRP nodes have two ports and are attached to two separated networks of similar topology. PRP can be implemented entirely in software, i.e.
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Lustre file system was first installed for production use in March 2003 on the MCR Linux Cluster at the Lawrence Livermore National Laboratory, one of the largest supercomputer at the time. Lustre 1.0.0 was released in December 2003, and provided basic Lustre filesystem functionality, including server failover and recovery. Lustre 1.2.
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PowerDNS is a DNS server program, written in C++ and licensed under the GPL. It runs on most Unix derivatives. PowerDNS features a large number of different backends ranging from simple BIND style zonefiles to relational databases and load balancing/failover algorithms. A DNS recursor is provided as a separate program.
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Today, UUCP is rarely used over dial-up links, but is occasionally used over TCP/IP. The number of systems involved, as of early 2006, ran between 1500 and 2000 sites across 60 enterprises. UUCP's longevity can be attributed to its low cost, extensive logging, native failover to dialup, and persistent queue management.
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Speedify is a mobile VPN bonding service available for devices running Windows, macOS, Android and iOS. Speedify 1.0 was first launched in June 2014 as a channel bonding service. Speedify can combine multiple Internet connections given its link aggregation capabilities. In theory, this should offer faster Internet connection speeds and failover protection.
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ServerNet is a switched fabric communications link primarily used in proprietary computers made by Tandem Computers, Compaq, and HP. Its features include good scalability, clean fault containment, error detection and failover. The ServerNet architecture specification defines a connection between nodes, either processor or high performance I/O nodes such as storage devices.
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Red Hat adapted the Piranha load balancing software to allow for transparent load balancing and failover between servers. The application being balanced does not require special configuration to be balanced, instead a Red Hat Enterprise Linux server with the load balancer configured, intercepts and routes traffic based on metrics/rules set on the load balancer.
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Recovery testing is simulating failure modes or actually causing failures in a controlled environment. Following a failure, the failover mechanism is tested to ensure that data is not lost or corrupted and that any agreed service levels are maintained (e.g., function availability or response times). Type or extent of recovery is specified in the requirement specifications.
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EDB is a member of the Red Hat OpenShift Primed Program with a set of two certified Linux Container images published in the Red Hat Container Catalog. One container is preconfigured with the EDB Postgres Advanced Server 9.5 database, EDB Postgres Failover Manager, and pgPool for load balancing. The other container is preconfigured with EDB Postgres Backup and Recovery.
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Similar to the migration mechanism described above, failover allows the VM to continue operations if the host fails. Generally it occurs if the migration has stopped working. However, in this case, the VM continues operation from the last-known coherent state, rather than the current state, based on whatever materials the backup server was last provided with.
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The DHCP ensures reliability in several ways: periodic renewal, rebinding, and failover. DHCP clients are allocated leases that last for some period of time. Clients begin to attempt to renew their leases once half the lease interval has expired. They do this by sending a unicast DHCPREQUEST message to the DHCP server that granted the original lease.
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24/7 services often employ complex schemes that ensure their resistance to potential disruption, resilience in the event of disruption, and minimum standards of overall reliability. Critical infrastructure may be supported by failover systems, electric generators, and satellite communications. In the event of catastrophic disaster, some 24/7 services prepare entirely redundant, parallel infrastructures, often in other geographic regions.
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S. cellular networks, and secure WiFi. GPS for applications such as Automatic Vehicle Location (AVL) sometimes commercial referred to as fleet tracking or Geo-Based Dispatch and Navigation. Connectivity to multiple simultaneous WAN via GIG ethernet, USB or WiFi paths with user-selectable order for failover and fail back. Access to 4 simultaneous WANS and GPS.
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Microsoft Cluster Server (MSCS) is a computer program that allows server computers to work together as a computer cluster, to provide failover and increased availability of applications, or parallel calculating power in case of high-performance computing (HPC) clusters (as in supercomputing). Microsoft has three technologies for clustering: Microsoft Cluster Service (MSCS, a HA clustering service), Component Load Balancing (CLB) (part of Application Center 2000), and Network Load Balancing Services (NLB). With the release of Windows Server 2008 the MSCS service was renamed to Windows Server Failover Clustering (WSFC), and the Component Load Balancing (CLB) feature became deprecated. Prior to Windows Server 2008, clustering required (per Microsoft KBs) that all nodes in the clusters to be as identical as possible from hardware, drivers, firmware, all the way to software.
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AireSpring is a super-carrier operating worldwide & nationwide managed services who provides cloud communications and managed connectivity services to businesses. Headquartered in Van Nuys, California, the company provides managed services including unified communications, voice, data, security, failover, network management and IP services to around 14,000 small, medium- sized, and multi-location enterprises in more than 80 major metropolitan markets across the United States.
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A DAG contains Mailbox servers that become members of the DAG. Once a Mailbox server is a member of a DAG, the Mailbox Databases on that server can be copied to other members of the DAG. When a Mailbox server is added to a DAG, the Failover Clustering Windows role is installed on the server and all required clustering resources are created.
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UltraBac - Provides file-by-file backup for basic standard data protection. Capabilities include active cluster server backup, email alerts, hardware failover functionality, and built-in encryption. UltraBac has options and agents like SQL, Exchange, Oracle, Media Libraries, Linux, Hyper-V, and vSphere. UBDR Gold - Using image, or snapshot technology, performs a bare metal restore in the event of an unrecoverable machine.
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Along with backup, Veeam Backup & Replication can perform image-based VM replication. It creates a “clone” of a production VM onsite or offsite and keeps it in a ready-to-use state. Each VM replica has a configurable number of failover points. Image-based VM replication is also available via Veeam Cloud Connect for Disaster Recovery as a Service (DRaaS).
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Slony-I is an asynchronous master-slave replication system for the PostgreSQL DBMS, providing support for cascading and failover. Asynchronous means that when a database transaction has been committed to the master server, it is not yet guaranteed to be available in slaves. Cascading means that replicas can be created (and updated) via other replicas, i.e. they needn't directly connect to the master.
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MOVEit is a managed file transfer software produced by Ipswitch, Inc. MOVEit encrypts files and uses secure File Transfer Protocols to transfer data with automation, analytics and failover options. The software has been used in the healthcare industry by companies such as Rochester Hospital and Medibank, as well as thousands of IT departments in financial services, high technology, and government.
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LDP is then used to create an equivalent mesh of PWs between those PEs. An advantage to using PWs as the underlying technology for the data plane is that in the event of failure, traffic will automatically be routed along available backup paths in the service provider's network. Failover will be much faster than could be achieved with e.g. Spanning Tree Protocol (STP).
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The data tier and application tier can exist on the same machine. To support scalability, the application tier can be load balanced and the data tier can be clustered. If using Microsoft SQL Server 2012 or later, AlwaysOn SQL Server Failover Clusters and Availability Groups are supported which allows for geographic replication of data. The primary container is the project collection.
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Windows NT Load Balancing Service (WLBS) is a feature of Windows NT that provides load balancing and clustering for applications. WLBS dynamically distributes IP traffic across multiple cluster nodes, and provides automatic failover in the event of node failure. WLBS was replaced by Network Load Balancing Services in Windows 2000. Auto fail over is also a part in this frame.
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This add-on in Ulteo OVD 3 allowed setting up two physical Session Managers and databases in a cold-standby cluster. Data was replicated between the two databases using DRBD, and failover was handled by the Heartbeat cluster manager. High Availability was a Gold module. It is no longer included in the source code for OVD 4, nor available from the Premium repository.
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In computer networking, the Hot Standby Router Protocol (HSRP) is a Cisco proprietary redundancy protocol for establishing a fault-tolerant default gateway. Version 1 of the protocol was described in in 1998. There is no RFC for version 2 of the protocol. The protocol establishes an association between gateways in order to achieve default gateway failover if the primary gateway becomes inaccessible.
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By default, snapshots are temporary; they do not survive a reboot. The ability to create persistent snapshots was added in Windows Server 2003 onward. However, Windows 8 removed the GUI portion necessary to browse them. () Windows software and services that support VSS include Windows Failover Cluster, Windows Server Backup, Hyper-V, Virtual Server, Active Directory, SQL Server, Exchange Server and SharePoint.
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Dead Peer Detection (DPD) is a method of detecting a dead Internet Key Exchange (IKE) peer. The method uses IPsec traffic patterns to minimize the number of messages required to confirm the availability of a peer. DPD is used to reclaim the lost resources in case a peer is found dead and it is also used to perform IKE peer failover.
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Load balancing can be useful in applications with redundant communications links. For example, a company may have multiple Internet connections ensuring network access if one of the connections fails. A failover arrangement would mean that one link is designated for normal use, while the second link is used only if the primary link fails. Using load balancing, both links can be in use all the time.
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Anycast is normally highly reliable, as it can provide automatic failover. Anycast applications typically feature external "heartbeat" monitoring of the server's function, and withdraw the route announcement if the server fails. In some cases this is done by the actual servers announcing the anycast prefix to the router over OSPF or another IGP. If the servers die, the router will automatically withdraw the announcement.
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The Common Address Redundancy Protocol or CARP is a computer networking protocol which allows multiple hosts on the same local area network to share a set of IP addresses. Its primary purpose is to provide failover redundancy, especially when used with firewalls and routers. In some configurations, CARP can also provide load balancing functionality. CARP provides functionality similar to VRRP and to Cisco Systems' HSRP.
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"Hitachi ditches monolithic storage," September 27, 2010, IT News Monolithic arrays provide failover benefits. The shared cache architecture of monolithic arrays ensures that if one cache module fails, another cache is used to process the user's request. However once you have more than a single system this architecture is complex and requires investment to manage and control the interactions between the different components.Evans, Chris.
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Xsan is a complete SAN solution that includes the metadata controller software, the file system client software, and integrated setup, management and monitoring tools. Xsan has all the normal features to be expected in an enterprise shared disk file system, including support for large files and file systems, multiple mounted file systems, metadata controller failover for fault tolerance, and support for multiple operating systems.
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The company provides converged voice and data products and services for the network security industry. It offers Tina, a single box product that delivers telephony services. The company also provides VoIP, unified threat management, connectivity failover, caching, URL filtering, and other communication products and services. It serves customers through its partner channels and resellers in the United Kingdom, North America, the Far East, and internationally.
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On 24 March, the European Wikipedia servers went offline due to an overheating problem. Failover to servers in Florida turned out to be broken, causing DNS resolution for Wikipedia to fail across the world. The problem was resolved quickly, but due to DNS caching effects, some areas were slower to regain access to Wikipedia than others. On 13 May, the site released a new interface.
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Many computer systems that were produced after the Tandem NonStop platform relied on some form of redundancy (or HOT backup) and a "failover" scheme to continue running. On the Tandem NonStop, however, each CPU performs its own work and may contain a dormant "backup" process for another CPU. Each pair of CPUs, 0 and 1 for example, share hardware ownership of controllers and disk drives. The drives are not REDUNDANT.
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ServiceMix is lightweight and easily embeddable, has integrated Spring Framework support and can be run at the edge of the network (inside a client or server), as a standalone ESB provider or as a service within another ESB. ServiceMix is compatible with Java SE or a Java EE application server. ServiceMix uses ActiveMQ to provide remoting, clustering, reliability and distributed failover. The basic frameworks used by ServiceMix are Spring and XBean.
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All data is maintained in memory (RAM), with data persistence ensured by write-ahead logging and snapshotting, and for those reasons some industry observers have compared Tarantool to Membase. Replication is asynchronous and failover (getting one Tarantool server to take over from another) is possible either from a replica server or from a "hot standby" server. There are no locks. Tarantool uses Lua-style coroutines and asynchronous I/O.
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The "E" (Error) bit – If set, the message contains a protocol error, and the message will not conform to the CCF described for this command. Messages with the "E" bit set are commonly referred to as error messages. This bit MUST NOT be set in request messages. The "T" (Potentially re-transmitted message) bit – This flag is set after a link failover procedure, to aid the removal of duplicate requests.
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High availability and recovery features enable transparent recovery in conjunction with failover servers. Since Lustre 2.10 the LNet Multi-Rail (MR) feature allows link aggregation of two or more network interfaces between a client and server to improve bandwidth. The LNet interface types do not need to be the same network type. In 2.12 Multi-Rail was enhanced to improve fault tolerance if multiple network interfaces are available between peers.
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The Metro Ring Protocol (MRP) is a Layer 2 resilience protocol developed by Foundry Networks and currently being delivered in products manufactured by Brocade Communications Systems and Hewlett Packard. The protocol quite tightly specifies a topology in which layer 2 devices, usually at the core of a larger network, are configured and as such is able to achieve much faster failover times than other Layer 2 protocols such as Spanning Tree.
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The box itself contains all the circuitry needed to split the data and voice channels. An Ethernet cable is run directly to the customer's PC or router, and the POTS lines within the home are connected to the POTS terminals inside the customer-premises equipment (CPE) unit. The CPE unit is powered from the telco's central office, and will continue to work during a power outage, and supports failover-to- POTS.
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In addition to the client–server model, distributed computing applications often use the peer-to-peer (P2P) application architecture. In the client–server model, the server is often designed to operate as a centralized system that serves many clients. The computing power, memory and storage requirements of a server must be scaled appropriately to the expected workload. Load-balancing and failover systems are often employed to scale the server beyond a single physical machine.
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Load balancing is often used to implement failover—the continuation of a service after the failure of one or more of its components. The components are monitored continually (e.g., web servers may be monitored by fetching known pages), and when one becomes non-responsive, the load balancer is informed and no longer sends traffic to it. When a component comes back online, the load balancer begins to route traffic to it again.
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Dataprobe is an American manufacturer of systems for minimizing downtime to critical data and communication networks.Disaster Recovery Journal, Maximizing IT Uptime When Disaster Strikes Dataprobe power control products allow remote management of AC and DC power for reboot, energy management and security. Redundancy switching systems provide T-1 and physical layer switchover and failover for equipment and circuit redundancy. Remote relay control integrates legacy systems that relay on contact closures into the network environment.
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With the cluster validation wizard, an administrator can run a set of focused tests on a collection of servers that are intended to use as nodes in a cluster. This cluster validation process tests the underlying hardware and software directly, and individually, to obtain an accurate assessment of how well failover clustering can be supported on a given configuration. This feature is only available in Enterprise and Datacenter editions of Windows Server.
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A hot spare or warm spare or hot standby is used as a failover mechanism to provide reliability in system configurations. The hot spare is active and connected as part of a working system. When a key component fails, the hot spare is switched into operation. More generally, a hot standby can be used to refer to any device or system that is held in readiness to overcome an otherwise significant start-up delay.
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SpaceWire replaced old PECL differential drivers in the physical layer of IEEE 1355 DS-DE by low-voltage differential signaling (LVDS). SpaceWire also proposes the use of space- qualified 9-pin connectors. SpaceWire and IEEE 1355 DS-DE allows for a wider set of speeds for data transmission, and some new features for automatic failover. The fail-over features let data find alternate routes, so a spacecraft can have multiple data buses, and be made fault-tolerant.
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AMB can thus compensate for signal deterioration by buffering and resending the signal. The AMB can also offer error correction, without imposing any additional overhead on the processor or the system's memory controller. It can also use the Bit Lane Failover Correction feature to identify bad data paths and remove them from operation, which dramatically reduces command/address errors. Also, since reads and writes are buffered, they can be done in parallel by the memory controller.
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Multiple switches in a fabric usually form a mesh network, with devices being on the "edges" ("leaves") of the mesh. Most Fibre Channel network designs employ two separate fabrics for redundancy. The two fabrics share the edge nodes (devices), but are otherwise unconnected. One of the advantages of such setup is capability of failover, meaning that in case one link breaks or a fabric goes out of order, datagrams can be sent via the second fabric.
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Computer equipment generates heat, and is sensitive to heat, humidity, and dust, but also the need for very high resilience and failover requirements. Maintaining a stable temperature and humidity within tight tolerances is critical to IT system reliability. In most server rooms "close control air conditioning" systems, also known as PAC (precision air conditioning) systems, are installed. These systems control temperature, humidity and particle filtration within tight tolerances 24 hours a day and can be remotely monitored.
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Server farms are increasingly being used instead of or in addition to mainframe computers by large enterprises, although server farms do not yet reach the same reliability levels as mainframes. Because of the sheer number of computers in large server farms, the failure of an individual machine is a commonplace event, and the management of large server farms needs to take this into account by providing support for redundancy, automatic failover, and rapid reconfiguration of the server cluster.
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This is usually achieved with a shared database or an in-memory session database, for example Memcached. One basic solution to the session data issue is to send all requests in a user session consistently to the same backend server. This is known as "persistence" or "stickiness". A significant downside to this technique is its lack of automatic failover: if a backend server goes down, its per-session information becomes inaccessible, and any sessions depending on it are lost.
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Cassandra is designed as a distributed system, for deployment of large numbers of nodes across multiple data centers. Key features of Cassandra’s distributed architecture are specifically tailored for multiple- data center deployment, for redundancy, for failover and disaster recovery. ; Scalability : Designed to have read and write throughput both increase linearly as new machines are added, with the aim of no downtime or interruption to applications. ; Fault-tolerant : Data is automatically replicated to multiple nodes for fault-tolerance.
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In computer data storage technology field, dynamic multipathing (DMP) is a multipath I/O enhancement technique that balances input/output (I/O) across many available paths from the computer to the storage device to improve performance and availability. The name was introduced with Veritas Volume Manager software. The DMP utility does not take any time to switch over, although the total time for failover is dependent on how long the underlying disk driver retries the command before giving up.
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All nodes in a GFS2 cluster function as peers. Using GFS2 in a cluster requires hardware to allow access to the shared storage, and a lock manager to control access to the storage. The lock manager operates as a separate module: thus GFS2 can use the Distributed Lock Manager (DLM) for cluster configurations and the "nolock" lock manager for local filesystems. Older versions of GFS also support GULM, a server-based lock manager which implements redundancy via failover.
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The new servers were dubbed the Code Generation Systems or CGS. They were initially six Sun-3/280 servers upgraded eventually to two Sun-4/690 servers for redundancy. A second pair of servers for catastrophic failover was also installed in Malvern, Pennsylvania and later moved to Norristown, Pennsylvania as part of later site consolidation efforts. After the migration, these servers managed source code and binary images for more than 6600 nodes and 38,000 customer interfaces worldwide.
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In such systems, the spare processors do not contribute to system throughput between failures, but merely redundantly execute exactly the same data thread as the active processor at the same instant, in "lock step". Faults are detected by seeing when the cloned processors' outputs diverged. To detect failures, the system must have two physical processors for each logical, active processor. To also implement automatic failover recovery, the system must have three or four physical processors for each logical processor.
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Simple DNS MX record based Mail Hub cluster with parallelism and front-end failover and load balancing is illustrated in the following diagram: Image:RAIS-Mail.jpg The servers would be all Linux x86 servers with low cost SATA or PATA hard disk storage. The front-end servers would most likely run Postfix with Spamassassin and ClamAV. This RAIS server Cluster would then overcome the problem with Perl based Spamassassin being too CPU and memory hungry for low cost servers.
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Carrier clouds encompass data centers at different network tiers and wide area networks that connect multiple data centers to each other as well as to the cloud users. Links between data centers are used, for instance, for failover, overflow, backup, and geographic diversity. Carrier clouds can be set up as public, private, or hybrid clouds. The carrier cloud federates these cloud entities, using a single management system to orchestrate, manage, and monitor data center and network resources as a single system.
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Large networks today tend to have a large number of entry points (for performance, failover, and other reasons). Furthermore, many sites employ internal firewalls to provide some form of compartmentalization. This makes administration particularly difficult, both from a practical point of view and with regard to policy consistency, since no unified and comprehensive management mechanism exists. End-to-end encryption can also be a threat to firewalls, as it prevents them from looking at the packet fields necessary to do filtering.
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They were initially six Sun-3 servers upgraded eventually to two Sun-4/690 servers for redundancy. A second pair of servers for catastrophic failover were also installed in Malvern, PA and later moved to Norristown, PA as part of later site consolidation efforts. After the migration, there was code for more than 6000 nodes and 38,000 customer interfaces. Tymnet was still growing, and at several times reached its peak capacity when some of its customers held network intensive events.
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Data Guard provides high availability for a database system. It can also reduce the human intervention required to switch between databases at disaster-recovery ("failover") or upgrade/maintenance ("switchover") time. Through the use of standby redo log files, Data Guard can minimize data loss. It supports heterogeneous configurations in which the primary and standby systems may have different CPU architectures, operating systems (for example, Microsoft Windows and Linux), operating-system binaries (32-bit/64-bit), or Oracle database binaries (32-bit/64-bit).
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He has worked in the anti-hacker field and with PCI compliance. Ciabarra founded Revel Systems with Lisa Falzone in 2010. Ciabarra developed the technology behind Revel’s iPad Point of sale and led the technological advancements as well as oversee data security of the system while employed at Revel. Ciabarra designed Revel Ethernet Connect, which provides failover connections between Wi-Fi and Ethernet. In 2016, Revel Systems was named the Leading iPad Point of Sale Company during Apple’s Q4 Financial Results Conference Call.
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It is now a server division within Hewlett Packard Enterprise, following Hewlett-Packard's acquisition of Compaq and the split of Hewlett Packard into HP Inc. and Hewlett Packard Enterprise. Tandem's NonStop systems use a number of independent identical processors and redundant storage devices and controllers to provide automatic high-speed "failover" in the case of a hardware or software failure. To contain the scope of failures and of corrupted data, these multi-computer systems have no shared central components, not even main memory.
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On the front end, VPLEX presents an interface to a host which looks like a standard storage controller SCSI target. On the VPLEX back end, the VPLEX provides an interface to a physical storage controller that act like a host, essentially like a SCSI initiator. A VPLEX cluster consists of one or more pairs of directors (up to 4 pairs). Any director from any engine can failover to any other director in the cluster in the case of hardware or path failure.
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Other members wishing to modify the data item must first contact the master node. Allowing only a single master makes it easier to achieve consistency among the members of the group, but is less flexible than multi-master replication. Multi-master replication can also be contrasted with failover clustering where passive slave servers are replicating the master data in order to prepare for takeover in the event that the master stops functioning. The master is the only server active for client interaction.
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GoAnywhere MFT's interface and workflow features help to eliminate the need for custom programs/scripts, single-function tools and manual processes that were traditionally needed. This improves the quality of file transfers and helps organizations to comply with data security policies and regulations. With integrated support for clustering, GoAnywhere MFT can process high volumes of file transfers for enterprises by load balancing processes across multiple systems. The clustering technology in GoAnywhere MFT also provides active-active automatic failover for disaster recovery.
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Nodes in an MC-LAG cluster communicate to synchronize and negotiate automatic switchovers (failover). Some implementations may support administrator-initiated (manual) switchovers. The diagram here shows four configurations: Illustration comparing LAG to high-availability MLAG # Switches A and B are each configured to group four discrete links (as indicated in green) into a single logical link with four times the bandwidth. Standard LACP protocol ensures that if any of the links go down, traffic will be distributed among the remaining three.
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By late 2000, a minor revision was done to the 200 series, and the email servers were renamed M200 Message Servers, dropping the SP and ES designations. A high-end version of the second generation chassis was introduced, the M2000, replacing the M1000 series. The M2000 followed the M1000 specs, in offering a large external RAID array and external UPS. The new twist was clustered failover, allowing two M2000 heads to connect to a single RAID array with redundant controllers.
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Icinga has been successfully deployed in large and complex environments with thousands of hosts and services, in distributed and failover setups. The software's modular architecture with standalone Core, Web and IDODB (Icinga Data Out Database) facilitate distributed monitoring and distributed systems monitoring. Nagios Remote Plugin Executor (NRPE) is an Icinga compatible agent that allows remote systems monitoring using scripts that are hosted on the remote systems. It allows for monitoring resources such as disk usage, system load or number of users currently logged in.
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Exchange Server Enterprise Edition supports clustering of up to 4 nodes when using Windows 2000 Server, and up to 8 nodes with Windows Server 2003. Exchange Server 2003 also introduced active-active clustering, but for two-node clusters only. In this setup, both servers in the cluster are allowed to be active simultaneously. This is opposed to Exchange's more common active-passive mode in which the failover servers in any cluster node cannot be used at all while their corresponding home servers are active.
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Big Brother has also been cited in a number of books on system administration, computer security, and networking. The application supports redundancy via multiple displays, as well as failover. Network elements can be tested from multiple locations and users can write custom tests. An open-source version of the project exists: between 2002 and 2004 it was called bbgen toolkit, between 2005 and 2008 it was called Hobbit, but to avoid breach of trademark, it was renamed Xymon which is still in development and use.
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IBM Spectrum Virtualize is a block storage virtualization system. Because the IBM Storwize V7000 uses SVC code, it can also be used to perform storage virtualization in exactly the same way as SVC. Since mid-2012 it offers real time compression with no performance impact, saving up to 80% of disk utilization. SVC can be configured on a Stretched Cluster Mode, with automatic failover between two datacenters and can have SSD (Solid State Drives) that can be used by EasyTier software to perform sub-LUN automatic tiering.
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Solaris Cluster provides services that remain available even when individual nodes or components of the cluster fail. Solaris Cluster provides two types of HA services: failover services and scalable services. To eliminate single points of failure, a Solaris Cluster configuration has redundant components, including multiple network connections and data storage which is multiply connected via a storage area network. Clustering software such as Solaris Cluster is a key component in a Business Continuity solution, and the Solaris Cluster Geographic Edition was created specifically to address that requirement.
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Up to 14 TXP and NonStop II systems could now be combined via FOX, a long-distance fault-tolerant fibre optic bus for connecting TNS clusters across a business campus; a cluster of clusters with a total of 224 CPUs. This allowed further scale-up for taking on the largest mainframe applications. Like the CPU modules within the computers, Guardian could failover entire task sets to other machines in the network. Worldwide clusters of 4000 CPUs could also be built via conventional long-haul network links.
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The filtering syntax is similar to IPFilter, with some modifications to make it clearer. Network Address Translation (NAT) and Quality of Service (QoS) have been integrated into PF. Features such as pfsync and CARP for failover and redundancy, authpf for session authentication, and ftp-proxy to ease firewalling the difficult FTP protocol, have also extended PF. Also PF supports SMP (Symmetric multiprocessing) & STO (Stateful Tracking Options). One of the many innovative features is PF's logging. PF's logging is configurable per rule within the pf.
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HERO Hosted PBX is composed of SIP Proxy, Registrar, and Presence server components that work together to allow real-time communication over IP networks. The software can be administered via web interface and is SIP-compliant), hence interoperable with other SIP devices and services. Other features include: Auto-Attendant IVR, emergency 911 support, integrated billing, cost & statistics reporting, device provisioning and failover and high availability support. In 2009, HERO Hosted PBX was named 'Best Service Provider Solution' by the Technology Marketing Corporation (TMC) at the annual ITEXPO West conference held in Los Angeles.
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This provides a fully redundant active-active configuration, with both storage processors serving requests and each acting as failover for the other so that initiators see the array as active-passive. An integrated UPS provides security for data in the event of power failure. Storage is fibre-attached, initiators may be fibre- or IP-attached, the architecture supports both on the same array depending on configuration. Storage is connected via back-end loops with up to 120 drives per loop, the drives are contained in Disk Array Enclosures (DAEs) of 15 drives each.
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Zetta provides cloud backup and disaster recovery"Zetta Launches Zetta Disaster Recovery Enabling Less- Than-Five Minute Failover from Anywhere", Zetta, 20 September 2016 services, on-premises backup and archiving and is most notable for its network efficient data transfer.Hardiman, Nick. "Cloud Backup and Disaster Recovery: The Zetta Approach", TechRepublic, 28 November 2012 It uses lightweight agent software to replicate customer data, creating a second copy in Zetta's bi-coastal enterprise-grade data centers that is available for recovery after a data loss event, such as a server crash or natural disaster.Vance, Jeff.
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Cyberoam’s product range offers network security (Firewall and UTM appliances), centralized security management (Cyberoam Central Console appliances), centralized visibility (Cyberoam iView ), and Cyberoam NetGenie for home and small office networks. Cyberoam network security appliances include multiple features like Firewall – VPN (SSL VPN & IPSec), Gateway Anti-Virus, Anti-Spyware & Anti-Spam, Intrusion Prevention System (IPS), Content & Application Filtering, Web Application Firewall, Application Visibility & Control, Bandwidth Management, Multiple Link Management for Load Balancing and Gateway Failover,Cyberoam CR1000ia-Product Review - By Peter Stephenson, SC Magazine, 5 Jan 2012 over a single platform.
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RabbitMQ is an open-source message-broker software (sometimes called message- oriented middleware) that originally implemented the Advanced Message Queuing Protocol (AMQP) and has since been extended with a plug-in architecture to support Streaming Text Oriented Messaging Protocol (STOMP), MQ Telemetry Transport (MQTT), and other protocols.Which protocols does RabbitMQ support? The RabbitMQ server program is written in the Erlang programming language and is built on the Open Telecom Platform framework for clustering and failover. Client libraries to interface with the broker are available for all major programming languages.
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SQL Server 2012's new features and enhancements include Always On SQL Server Failover Cluster Instances and Availability Groups which provides a set of options to improve database availability, Contained Databases which simplify the moving of databases between instances, new and modified Dynamic Management Views and Functions, programmability enhancements including new spatial features, metadata discovery, sequence objects and the THROW statement, performance enhancements such as ColumnStore Indexes as well as improvements to OnLine and partition level operations and security enhancements including provisioning during setup, new permissions, improved role management, and default schema assignment for groups.
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The multiplex set-up provides scalability and High Availability for compute nodes because a multiplex coordinator node can failover to an alternate coordinator node. The SAP IQ Virtual Backup also allows users to quickly backup data, and along with storage replication technology, data is continuously copied so backups can occur quickly and “behind the scenes”. Once virtual backups are completed they can be verified through test and restore; enterprise data can be copied for development and testing. Then all that's left is to complete the backup at a transactionally consistent point in time.
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The term "failover", although probably in use by engineers much earlier, can be found in a 1962 declassified NASA report.NASA Postlaunch Memorandum Report for Mercury-Atlas, June 15, 1962. The term "switchover" can be found in the 1950sPetroleum Engineer for Management - Volume 31 - Page D-40 when describing '"Hot" and "Cold" Standby Systems', with the current meaning of immediate switchover to a running system (hot) and delayed switchover to a system that needs starting (cold). A conference proceedings from 1957 describes computer systems with both Emergency Switchover (i.e.
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Changes to it are replicated to other instances, and one of those instances becomes the new master when the old master fails. Paxos and Raft are more complex protocols that exist to solve problems with transient effects during failover, such as two instances thinking they are the master at the same time. Secret sharing is useful if failures of whole nodes are very common. This moves synchronization from an explicit recovery process to being part of each read, where a read of some data requires retrieving encoded data from several different nodes.
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Processes sending messages to a message queue are unaware of the identity of the receiving process; therefore, the process that was originally receiving these messages may have been replaced by another process during a failover or switch-over. Message queues can be grouped together to form message queue groups. Message queue groups permit multipoint-to-multipoint communication. They are identified by logical names so that a sender process is unaware of the number of message queues and of the location of the message queues within the cluster with which it is communicating.
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The Oracle Database Appliance runs Oracle Linux, Oracle Grid Infrastructure for cluster- and storage-management, and a choice of Oracle Enterprise Edition, Oracle Real Application Clusters (RAC) One Node, or Oracle RAC. These latter two database products leverage the clustered nature of the hardware to provide database-service failover in the event of a failure. Oracle Corporation also provides Oracle Clusterware for high- availability monitoring and cluster membership, and Oracle Automatic Storage Management (ASM) for storage- and disk-management. Oracle Appliance Kit (OAK) software offers a built-in management interface.
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Each AMS2000 model comes with dual controllers that automate many storage management tasks. The symmetric active/active architecture with dynamic load balancing provides integrated, automated, front-to-back-end I/O load balancing. In this design both controllers are active and able to dynamically access any volume from a host port on either controller with no penalty on performance. By eliminating the need for each volume to be assigned to an owning controller, servers can be connected to either controller on an AMS2000 without establishing a primary and failover path to their volumes.
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EtherChannel between a switch and a server. EtherChannel is a port link aggregation technology or port-channel architecture used primarily on Cisco switches. It allows grouping of several physical Ethernet links to create one logical Ethernet link for the purpose of providing fault-tolerance and high- speed links between switches, routers and servers. An EtherChannel can be created from between two and eight active Fast, Gigabit or 10-Gigabit Ethernet ports, with an additional one to eight inactive (failover) ports which become active as the other active ports fail.
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In general, a network utilizing Active Directory has more than one licensed Windows server computer. Backup and restore of Active Directory is possible for a network with a single domain controller, but Microsoft recommends more than one domain controller to provide automatic failover protection of the directory. Domain controllers are also ideally single-purpose for directory operations only, and should not run any other software or role. Certain Microsoft products such as SQL Server and Exchange can interfere with the operation of a domain controller, necessitating isolation of these products on additional Windows servers.
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NEBS Level 3 has strict specifications for fire suppression, thermal margin testing, vibration resistance (earthquakes), airflow patterns, acoustic limits, failover and partial operational requirements (such as chassis fan failures), failure severity levels, RF emissions and tolerances, and testing/certification requirements. NOTE: # Verizon and AT&T; do not follow NEBS Level 3 or SR-3580. They use their own NEBS checklist, Verizon Checklist (in MS Word format) and AT&T; Checklist, that details what they believe are important to their network's integrity. Both accept the TCG Checklist that can be found at those websites.
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Internally MySQL Cluster uses synchronous replication through a two-phase commit mechanism in order to guarantee that data is written to multiple nodes upon committing the data. (This is in contrast to what is usually referred to as "MySQL Replication", which is .) Two copies (known as replicas) of the data are required to guarantee availability. MySQL Cluster automatically creates “node groups” from the number of replicas and data nodes specified by the user. Updates are synchronously replicated between members of the node group to protect against data loss and support fast failover between nodes.
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The AT&T; StarServer E could still beat the comparably equipped NCR 3450 by 11% in the TPC Benchmark B test, and some of the SSE's 7 patented innovations were then adapted and retrofitted into the NCR 3000 design. NCR was renamed AT&T; Global Information Solutions (AT&T-GIS;) in 1994, and some of the top NCR management was purged. The Naperville, IL operation provided LifeKeeper Fault Resilient System software (a failover high-availability software cluster product), the Distributed lock manager for Oracle Parallel Server, and the Vistium computer-telephony integrated (CTI) on-line hardware-assisted networked meeting product.
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An analogy can be drawn between the concept of a server hypervisor and the concept of a storage hypervisor. By virtualizing servers, server hypervisors (VMware ESX, Microsoft Hyper-V, Citrix Hypervisor, Linux KVM, Xen) increased the utilization rates for server resources, and provided management flexibility by de-coupling servers from hardware. This led to cost savings in server infrastructure since fewer physical servers were needed to handle the same workload, and provided flexibility in administrative operations like backup, failover and disaster recovery. A storage hypervisor does for storage resources what the server hypervisor did for server resources.
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As a heartbeat is intended to be used to indicate the health of a machine, it is important that the heartbeat protocol and the transport that it runs on is as reliable as possible. Causing a failover because of a false alarm may, depending on the resource, be highly undesirable. It is also important to react quickly to an actual failure, so again it is important that the heartbeat is reliable. For this reason it is often desirable to have heartbeat running over more than one transport; for instance, an Ethernet segment using UDP/IP, and a serial link.
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ICCP is a real time data exchange protocol providing features for data transfer, monitoring and control. For a complete ICCP link there need to be facilities to manage and configure the link and monitor its performance. The ICCP standard does not specify any interface or requirements for these features that are necessary but nevertheless do not affect interoperability. Similarly failover and redundancy schemes and the way the SCADA responds to ICCP requests is not a protocol issue so is not specified. These non protocol specific features are referred to in the standard as “local implementation issues”.
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At the server level, failover automation usually uses a "heartbeat" system that connects two servers, either through using a separate cable (for example, RS-232 serial ports/cable) or a network connection. As long as a regular "pulse" or "heartbeat" continues between the main server and the second server, the second server will not bring its systems online. There may also be a third "spare parts" server that has running spare components for "hot" switching to prevent downtime. The second server takes over the work of the first as soon as it detects an alteration in the "heartbeat" of the first machine.
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The Hop-by-Hop Identifier is an unsigned 32-bit integer field (in network byte order) that is used to match the requests with their answers as the same value in the request is used in the response. The Diameter protocol requires that relaying and proxying agents maintain transaction state, which is used for failover purposes. Transaction state implies that upon forwarding a request, its Hop-by-Hop Identifier is saved; the field is replaced with a locally unique identifier, which is restored to its original value when the corresponding answer is received. The request’s state is released upon receipt of the answer.
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The MCAT creates a single Global Namespace across all Storage Resources connected to it so users and administrators can search for, access, and move data across multiple heterogeneous storage systems from multiple vendors across geographically dispersed data centers. The MCAT is connected to and interacts with a relational database management system to support its operation. Multiple MCATs can be deployed for horizontal scale-out and failover. Various Clients can interact with Nirvana including the supplied Web browser and Java based GUI Clients, a Command Line Interface, a native Windows virtual network drive interface, and user-developed applications via supplied APIs.
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Depending on the volume of messages that are required to be pushed, means to connect to the SMSC could be different, such as using simple modems or connecting over leased line using low level communication protocols (like SMPP, UCP etc.) Advanced SMS banking solutions also cater to providing failover mechanisms and least-cost routing options. Most online banking platforms are owned and developed by the banks using them. There is only one open source online banking platform supporting mobile banking and SMS payments called Cyclos, which is developed to stimulate and empower local banks in development countries.
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The Checkpoint Service provides a facility for processes to record checkpoint data incrementally, which can be used to protect an application against failures. When a process recovers from a failure (with a restart or a failover procedure), the Checkpoint Service can be used to retrieve the previously checkpointed data and resume execution from the recorded state, thus minimizing the impact of the failure. Checkpoints are cluster-wide entities. A copy of the data stored in a checkpoint is called a checkpoint replica, which is typically stored in main memory rather than on disk for performance reasons.
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These two key features help to ensure that no single point of failure exists in the deployment, and that the OpenAM service is always available to end-users. Redundant OpenAM servers, policy agents, and load balancers prevent a single point of failure. Session failover ensures the user's session continues uninterrupted, and no user data is lost. ; Developer access: OpenAM provides client application programming interfaces with Java and C APIs and a RESTful API that can return JSON or XML over HTTP, allowing users to access authentication, authorization, and identity services from web applications using REST clients in their language of choice.
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Ultimately, it is used to decrease hardware costs by condensing a failover cluster to a single machine, thus decreasing costs dramatically while providing the same services. Server roles and features are generally designed to operate in isolation. For example, Windows Server 2019 requires a certificate authority and a domain controller to exist on independent servers with independent instances of Windows Server. This is because additional roles and features adds areas of potential failure as well as adding visible security risks (placing a certificate authority on a domain controller poses the potential for root access to the root certificate).
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This means that some servers in the environment can serve as failover candidates while other servers can meet other requirements such as managing a subset of columns or tables for a departmental solution, a subset of rows for a geographical region or one-way replication for a reporting server. In the event of a source, target, or network failure, data integrity is enforced through this two-phase commit protocol by ensuring that either the whole transaction is replicated, or none of it is. In addition, Ingres Replicator can operate over RDBMS’s from multiple vendors to connect them.
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Like Advanced Server, it supports clustering, failover and load balancing. Its minimum system requirements are normal, but it was designed to be capable of handing advanced, fault-tolerant and scalable hardware—for instance computers with up to 32 CPUs and 32GBs RAM, with rigorous system testing and qualification, hardware partitioning, coordinated maintenance and change control. System requirements are similar to those of Windows 2000 Advanced Server, however they may need to be higher to scale to larger infrastructure. Windows 2000 Datacenter Server was released to manufacturing on August 11, 2000 and launched on September 26, 2000.
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Windows Storage Server 2003 NAS equipment can be headless, which means that they are without any monitors, keyboards or mice, and are administered remotely. Such devices are plugged into any existing IP network and the storage capacity is available to all users. Windows Storage Server 2003 can use RAID arrays to provide data redundancy, fault-tolerance and high performance. Multiple such NAS servers can be clustered to appear as a single device, which allows responsibility for serving clients to be shared in such a way that if one server fails then other servers can take over (often termed a failover) which also improves fault-tolerance.
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Federation in Ganglia is achieved using a tree of point-to-point connections amongst representative cluster nodes to aggregate the state of multiple clusters. At each node in the tree, a Ganglia Meta Daemon (gmetad) periodically polls a collection of child data sources, parses the collected XML, saves all numeric, volatile metrics to round-robin databases and exports the aggregated XML over a TCP socket to clients. Data sources may be either gmond daemons, representing specific clusters, or other gmetad daemons, representing sets of clusters. Data sources use source IP addresses for access control and can be specified using multiple IP addresses for failover.
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High-availability Seamless Redundancy (HSR) is a network protocol for Ethernet that provides seamless failover against failure of any network component. This redundancy is invisible to the application. HSR nodes have two ports and act as a switch (bridge), which allows arranging them into a ring or meshed structure without dedicated switches. This is in contrast to the companion standard Parallel Redundancy Protocol (IEC 62439-3 Clause 4), with which HSR shares the operating principle. PRP and HSR are standardized by the IEC 62439-3:2016International Electrotechnical Commission IEC 62439-3:2016 Industrial communication networks - High availability automation networks - Part 3: Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR)).
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A reviewer guide published by the company describes several areas of improvement in R2. These include new virtualization capabilities (Live Migration, Cluster Shared Volumes using Failover Clustering and Hyper-V), reduced power consumption, a new set of management tools and new Active Directory capabilities such as a "recycle bin" for deleted objects. IIS 7.5 has been added to this release which also includes updated FTP server services. Security enhancements include encrypted clientless authenticated VPN services through DirectAccess for clients using Windows 7, and the addition of DNSSEC support for DNS Server Service. Even though DNSSEC as such is supported, only one signature algorithm is available: #5/RSA/SHA-1.
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Keys may be backed up in wrapped form and stored on a computer disk or other media, or externally using a secure portable device like a smartcard or some other security token. HSMs are used for real time authorisation and authentication in critical infrastructure so are typically engineered to support standard high availabilty models including clustering, automated failover, and redundant field-replaceable components. A few of the HSMs available in the market have the capability to execute specially developed modules within the HSM's secure enclosure. Such an ability is useful, for example, in cases where special algorithms or business logic has to be executed in a secured and controlled environment.
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Only NVLOGs in HA storage systems is replicated synchronously between two controllers for HA storage system failover capability, which helps to reduce overall system memory protection overheads. In a storage system with two controllers in HA configuration or MetroCluster with one controller on each site, each of the two controllers divides its own non-volatile memory into two pieces: local and its partner. In MetroCluster configuration with four nodes, each non-volatile memory divided into next pieces: local, local partner's and remote partner's. Starting with the All-Flash FAS A800 system, NetApp replaced the NVRAM PCI module with NVDIMMs connected to the memory bus, increasing the performance.
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The Virtual Switch Redundancy Protocol (VSRP) is a proprietary network resilience protocol developed by Foundry Networks and currently being sold in products manufactured by both Brocade Communications Systems (formerly Foundry Networks) and Hewlett Packard. The protocol differs from many others in use as it combines Layer 2 and Layer 3 resilience – effectively doing the jobs of both Spanning tree protocol and the Virtual Router Redundancy Protocol at the same time. Whilst the restrictions on the physical topologies able to make use of VSRP mean that it is less flexible than STP and VRRP it does significantly improve on the failover times provided by either of those protocols.
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Combining them can make configuration or troubleshooting of either the domain controller or the other installed software more difficult. A business intending to implement Active Directory is therefore recommended to purchase a number of Windows server licenses, to provide for at least two separate domain controllers, and optionally, additional domain controllers for performance or redundancy, a separate file server, a separate Exchange server, a separate SQL Server, and so forth to support the various server roles. Physical hardware costs for the many separate servers can be reduced through the use of virtualization, although for proper failover protection, Microsoft recommends not running multiple virtualized domain controllers on the same physical hardware.
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High-availability clusters (also known as HA clusters , fail-over clusters or Metroclusters Active/Active) are groups of computers that support server applications that can be reliably utilized with a minimum amount of down-time. They operate by using high availability software to harness redundant computers in groups or clusters that provide continued service when system components fail. Without clustering, if a server running a particular application crashes, the application will be unavailable until the crashed server is fixed. HA clustering remedies this situation by detecting hardware/software faults, and immediately restarting the application on another system without requiring administrative intervention, a process known as failover.
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IDIS Solution Suite is a full featured video management system (VMS) universally compatible with recording platforms, designed to be responsive and cost- effective by using a modular format, where customers only purchase the feature sets they need, such as recording, backup, redundant recording, failover, and video wall services. DirectCX is IDIS's HD-TVI offering, providing FHD over coaxial cabling, with support for HD-TVI 2.0. DirectCX cameras, recorders, and IDIS Solution Suite are designed to complement existing investments in coaxial cabling, if a complete remake of surveillance technology is not desired. A common, virtually-identical user interface (GUI) across all IDIS products is a distinguishing feature promoted by the company.
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LAG N is the load sharing mode of LAG and LAG N+N provides the worker standby flavour. The LAG N protocol automatically distributes and load balances the traffic across the working links within a LAG, thus maximising the use of the group if Ethernet links go down or come back up, providing improved resilience and throughput. For a different style of resilience between 2 nodes, a complete implementation of the LACP protocol supports separate worker/standby LAG subgroups. For LAG N+N, the worker links as a group will failover to the standby links if any one or more or all of the links in the worker group fail.
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A Server Core machine can be configured for several basic roles: Active Directory Domain Services, Active Directory Application Mode (ADAM), DNS Server, DHCP server, file server, print server, Windows Media Server, IIS 7 web server and Hyper-V virtual server. Server Core can also be used to create a cluster with high availability using failover clustering or network load balancing. As Server Core is not a different version of Windows Server 2008, but simply an installation option, it has the same file versions and default configurations as the full server version. In Windows Server 2008 and 2008 R2, if a server was installed as Server Core, it cannot be changed to the full GUI version and vice versa.
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Hosted Desktops are most often based on a Windows Server 2008 utilising Remote Desktop Services, often with an additional management layer from Vendors like Citrix Systems or Parallels Workstation to make personalisation easier. Licensing for this type of Hosted Desktop is provided by the Microsoft Service Provider License Agreement (SPLA), a special type of End-user license agreement. The user rents the appropriate licenses as part of the monthly fee paid to the service provider and receives automatic upgrade rights to the latest version of the software as part of the agreement. Backup and disaster recovery will be handled by the Hosted Desktop vendor; with the best solutions also providing failover to alternate datacentres.
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The widespread addition of WAN optimization devices is having an adverse effect on most network monitoring tools, especially when it comes to measuring accurate end-to-end delay because they limit round-trip delay time visibility. Status request failures, such as when a connection cannot be established, it times- out, or the document or message cannot be retrieved, usually produce an action from the monitoring system. These actions vary; An alarm may be sent (via SMS, email, etc.) to the resident sysadmin, automatic failover systems may be activated to remove the troubled server from duty until it can be repaired, etc. Monitoring the performance of a network uplink is also known as network traffic measurement.
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In 2018, one of the world's first smart houses was built in Klaukkala, Finland in the form of a five-floor apartment block, utilizing the Kone Residential Flow solution created by KONE, allowing even a smartphone to act as a home key. Commercial and industrial buildings have historically relied on robust proven protocols (like BACnet) while proprietary protocols (like X-10) were used in homes. Recent IEEE standards (notably IEEE 802.15.4, IEEE 1901 and IEEE 1905.1, IEEE 802.21, IEEE 802.11ac, IEEE 802.3at) and consortia efforts like nVoy (which verifies IEEE 1905.1 compliance) or QIVICON have provided a standards-based foundation for heterogeneous networking of many devices on many physical networks for diverse purposes, and quality of service and failover guarantees appropriate to support human health and safety.
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The client may re-export a native-protocol mount, for example via the kernel NFSv4 server, SAMBA, or the object-based OpenStack Storage (Swift) protocol using the "UFO" (Unified File and Object) translator. Most of the functionality of GlusterFS is implemented as translators, including file-based mirroring and replication, file-based striping, file-based load balancing, volume failover, scheduling and disk caching, storage quotas, and volume snapshots with user serviceability (since GlusterFS version 3.6). The GlusterFS server is intentionally kept simple: it exports an existing directory as-is, leaving it up to client-side translators to structure the store. The clients themselves are stateless, do not communicate with each other, and are expected to have translator configurations consistent with each other.
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Adding more components to an overall system design can undermine efforts to achieve high availability because complex systems inherently have more potential failure points and are more difficult to implement correctly. While some analysts would put forth the theory that the most highly available systems adhere to a simple architecture (a single, high quality, multi-purpose physical system with comprehensive internal hardware redundancy), this architecture suffers from the requirement that the entire system must be brought down for patching and operating system upgrades. More advanced system designs allow for systems to be patched and upgraded without compromising service availability (see load balancing and failover). High availability requires less human intervention to restore operation in complex systems; the reason for this being that the most common cause for outages is human error.
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Internet of things has been described as a "network of networks" where internal workings of one network may not be appropriate to disclose to a peer or foreign network. For example, a use case involving redundant or spare IoT devices facilitates availability and serviceability objectives, but network operations that load balances or replaces different devices need not be reflected to peer or foreign networks that "share" a device across network contexts. The peer expects a particular type of service or data structure but likely doesn't need to know about device failover, replacement or repair. EPID can be used to share a common public key or certificate that describes and attests the group of similar devices used for redundancy and availability, but doesn't allow tracking of specific device movements.
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Using allows the deployment of single or multiple containers cluster-wide, with more advanced options including redundancy, failover, deployment to specific cluster members, dependencies between containers, and grouped deployment of containers. A command-line utility called is used to configure and monitor this distributed init system; internally, it communicates with the daemon using a JSON-based API on top of HTTP, which may also be used directly. When used locally on a cluster member, communicates with the local instance over a Unix domain socket; when used from an external host, SSH tunneling is used with authentication provided through public SSH keys. All of the above-mentioned daemons and command-line utilities (, , and ) are written in the Go language and distributed under the terms of the Apache License 2.0.
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It is anticipated that powerline networking functionality will be embedded in TVs, set-top boxes, DVRs, and other consumer electronics, especially with the emergence of global powerline networking standards such as the IEEE 1901 standard, ratified in September 2010. Several manufacturers sell devices that include 802.11n, HomePlug and four ports of gigabit ethernet connectivity for under US$100. Several are announced for early 2013 that also include 802.11ac connectivity, the combination of which with HomePlug is sold by Qualcomm Atheros as its Hy-Fi hybrid networking technology, an implementation of IEEE P1905. This permits a device to use wired ethernet, powerline or wireless communication as available to provide a redundant and reliable failover thought to be particularly important in consumer applications where there is no onsite expertise typically available to debug connections.
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NET Framework, Internet Explorer, Windows PowerShell or many other features not related to core server features. A Server Core installation can be configured for several basic roles, including the domain controller (Active Directory Domain Services), Active Directory Lightweight Directory Services (formerly known as Active Directory Application Mode), DNS Server, DHCP server, file server, print server, Windows Media Server, Internet Information Services 7 web server and Hyper-V virtual server roles. Server Core can also be used to create a cluster with high availability using failover clustering or network load balancing. Andrew Mason, a program manager on the Windows Server team, noted that a primary motivation for producing a Server Core variant of Windows Server 2008 was to reduce the attack surface of the operating system, and that about 70% of the security vulnerabilities in Microsoft Windows from the prior five years would not have affected Server Core.
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In terrestrial point to point microwave systems ranging from 11 GHz to 80 GHz, a parallel backup link can be installed alongside a rain fade prone higher bandwidth connection. In this arrangement, a primary link such as an 80 GHz 1 Gbit/s full duplex microwave bridge may be calculated to have a 99.9% availability rate over the period of one year. The calculated 99.9% availability rate means that the link may be down for a cumulative total of ten or more hours per year as the peaks of rain storms pass over the area. A secondary lower bandwidth link such as a 5.8 GHz based 100 Mbit/s bridge may be installed parallel to the primary link, with routers on both ends controlling automatic failover to the 100 Mbit/s bridge when the primary 1 Gbit/s link is down due to rain fade.
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Lustre file system high availability features include a robust failover and recovery mechanism, making server failures and reboots transparent. Version interoperability between successive minor versions of the Lustre software enables a server to be upgraded by taking it offline (or failing it over to a standby server), performing the upgrade, and restarting it, while all active jobs continue to run, experiencing a delay while the backup server takes over the storage. Lustre MDSes are configured as an active/passive pair exporting a single MDT, or one or more active/active MDS pairs with DNE exporting two or more separate MDTs, while OSSes are typically deployed in an active/active configuration exporting separate OSTs to provide redundancy without extra system overhead. In single-MDT filesystems, the standby MDS for one filesystem is the MGS and/or monitoring node, or the active MDS for another file system, so no nodes are idle in the cluster.
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