HP Cluster Software manual Node Majority with File Share Witness

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This ensures that more than 50% of the nodes will have an up-to-date copy of the configuration information.

The cluster service does not start (and bring resources online) if there are 50% or less of the configured nodes up and running. The cluster service waits, trying to restart, until a quorum is established when more nodes join. This feature guarantees that the cluster has the latest and most up-to-date configuration. This also means that, in a geographically dispersed cluster, you must distribute the nodes evenly between two data centers and have an arbitrator node in a third site or separate protected area to be able to survive a single data center failure.

Node Majority with File Share Witness

The file share witness feature is an improvement to the Node Majority quorum model. This feature lets you use a file share that is external to the cluster as an additional "vote" to determine the status of the cluster in a Node Majority quorum cluster deployment.

Consider a two-node Node Majority quorum cluster. Because an Node Majority quorum cluster can only run when the majority of the cluster nodes are available, a two-node Node Majority quorum cluster is unable to sustain the failure of any cluster node. This is because the majority of a two-node cluster is two. To sustain the failure of any one node in an Node Majority quorum cluster, you must have at least three devices that can be considered as available. The file share witness feature enables you to use an external file share as a witness. This witness acts as the third available device in a two-node Node Majority quorum cluster. Therefore, with this feature enabled, a two-node Node Majority quorum cluster can sustain the failure of a single cluster node. Additionally, the file share witness feature provides the following two functions:

•It helps protect the cluster against a problem that is known as a split brain. This problem occurs if the two nodes in a Node Majority quorum cluster cannot communicate with each other. In this situation, each cluster node is unable to determine whether the loss of communication occurred because the other cluster node failed, or whether the loss of communication occurred because of a problem with the network. The file share witness can designate one of the cluster nodes as the surviving cluster node. That cluster node can then determine that it should continue to run the cluster. In this scenario, the surviving cluster node can determine that the other cluster node failed, or that the other cluster node was not sanctioned by the file share witness.

•It helps protect the cluster against a problem that is known as a partition in time. This problem occurs if the following conditions are true:

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Cluster node A is running, but cluster node B is not running.

Cluster node A stops running.

Cluster node B tries to run the cluster.

In this situation, cluster node B may not have the cluster state information that was updated on cluster node A. Therefore, cluster node B may run the cluster by using incorrect state information. The file share witness feature helps prevent this problem by detecting that the cluster state has changed. The file share witness feature prevents the cluster node that contains outdated cluster state information from running the cluster.

NOTE: See Microsoft documentation for more details on Microsoft Failover quorum configuration.

Cluster Shared Volume for Windows Server 2012

Cluster Shared Volume is a feature of Microsoft Failover Cluster which allows all nodes in the cluster with the ability to directly access the same volume without changing ownership of the disk resource. The result of the feature is that all nodes in a cluster can use the same volume to host actively running Virtual Machines at the same time. CSV manages storage access differently than regular clustered disks. CSV Volume is a shared disk containing NTFS partitions. CSV gives you the ability to store multiple VHDs on a single LUN and run the associated VMs on any cluster node.

Planning for HP 3PAR Cluster Extension 13

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Contents HP 3PAR Cluster Extension Software Administrator Guide Acknowledgments Contents CLI commands and utilities Support and other resources TroubleshootingGlossary Index CLI for easy integration Integration into cluster software Graphical user interfaceDisaster tolerance through geographical dispersion Metropolitan distance support Automated redirection of mirrored disksSynchronous mode support No server rebootStorage system configurations Fully Automatic Failover and FailbackTo-1 configuration To-1 configurationProcesses and components To-1 and 1-to-N configurationsHP 3PAR Remote Copy Remote Copy pairs Remote Copy volume groupsCluster setup considerations User configuration filePlanning for HP 3PAR Cluster Extension Force FlagNode Majority with File Share Witness 14 HP 3PAR Cluster Extension features HP 3PAR InForm Management Console or HP 3PAR InForm CLI Configuration tool clx3PARconfig.exeIP network considerations SAN fabric considerationsStarting the HP 3PAR Configuration Tool Configuring HP 3PAR Cluster ExtensionIntegrating HP 3PAR Cluster Extension with Msfc Defining the HP 3PAR configuration information using the GUI Configuring HP 3PAR Cluster Extension SystemUser.pwd Defining the HP 3PAR configuration information using the CLI Adding a HP 3PAR Cluster Extension resource Importing and exporting configuration informationExample Adding HP 3PAR Cluster Extension resource using cluster.exeChanging a HP 3PAR Cluster Extension resource name Configuring HP 3PAR Cluster Extension resourcesTIP Setting resource properties and values in the GUI Service or application properties and values Using Failover Cluster Management to set resource properties Make the necessary parameter changes, and then click OK Page Configuring cluster node data center assignments Configuring HP 3PAR storage system Changing Remote Copy volume group settings Selecting a volume groupConfiguring takeover actions Cluster resource clxfileshare /privprop Setting HP 3PAR Cluster Extension properties using a UCFSet-ClusterParameter -Name propertyname -Value valuetoset Adding dependencies on a HP 3PAR Cluster Extension resource Adding dependencies using Failover Cluster ManagementAdding dependencies using the PowerShell Adding dependencies using the CLICluster resource Disk32b00b /adddependencyclxfileshare Disaster-tolerant configuration example using a file share Configuration of HP 3PAR CLX for CSV disk on Windows ServerFour nodes host1DCA, host2DCA, host3DCB and host4DCB Service or application example Bringing a resource online Managing HP 3PAR Cluster Extension resourcesDisk3PARLUN25 \cluster resource Clxfileshare /ProP RestartAction=0Taking a resource offline Using Hyper-V Live Migration with HP 3PAR Cluster ExtensionDeleting a resource Creating array password file Bouncing service or applicationTiming considerations for Windows Clustering Msfc Administration Logs System resourcesHyper-V Live Migration log entries Configuring HP 3PAR Cluster Extension Page Configuring HP 3PAR Cluster Extension Windows Clustering User configuration fileFile structure ProgramFiles%\Hewlett-Packard\Cluster Extension 3PAR\confSpecifying object values Common objectsLogDir Application objectsLogLevel ApplicationDirApplicationStartup Optional Default %HPCLX3PARPATH% valuesClusterNotifyWaitTime ClusterNotifyCheckTimeDCAHosts Required DCBHosts RequiredRCVolumeGroupB Required RCVolumeGroupA RequiredDCA InServStorageSerNum Required DCB InServStorageSerNum RequiredResyncWaitTimeout Optional Sample configuration fileHP3PARCLICommandTimeout StatusRefreshIntervalPage Clx3PARrun CLI commandsConfiguring the HP 3PAR storage system Configuring the CLICreating the HP 3PAR Remote Copy environment Forceflag optionCreating and configuring the user configuration file Installing HP 3PAR InForm Command Line Interface CLITiming considerations Restrictions for customized implementations CSVDiskName String Synopsis\PSAdd-CSVDependencyOnCLX3PAR Outputs\PSAdd-CSVDependencyOnCLX3PAR -CSVDiskName Cluster Disk Related Links \PSAdd-VMDependencyOnCLX3PAR \PSAdd-VMDependencyOnCLX3PAR -CSVDiskName Cluster Disk Total virtual machines in the cluster residing on CSVRelated Links Name \PSGet-VMOnClusterSharedVolumeListForCLX3PAR Pre-execution and post-execution programs Post-execution return codes Pre-execution return codesLog facility LogsCLX cmdlet logs %HPCLX3PARPATH%\log\CLXCmdlet.log ProgramFiles%\Hewlett-Packard\Cluster Extension 3PAR\log\HP 3PAR Cluster Extension logs HP 3PAR storage system log or sysmgr log Error return codesRun showsys Log files Start errorsMsfc log file %windir\cluster\reports\cluster.log Failover error handling Echo rescan diskpart Cannot connect to HP 3PAR storage systemPing storage system network name or IP address Nslookup storage system network nameHost persona settings Change of HP 3PAR storage system IP or password fileNofailwrtonerr settings Cluster Extension Autopass troubleshooting Promote issueHP 3PAR Target arrays not configured with Remote Copy Links Remote Copy and 3PAR Virtual DomainsHP 3PAR Target arrays not configured with Remote Copy Links New and changed information in this edition Contacting HPRelated information WhitepapersDocument conventions Typographic conventionsGlossary Index SymbolsIndex Product manuals
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Cluster Software specifications

HP Cluster Software is a robust solution designed to enhance the reliability, availability, and scalability of computing environments in enterprise settings. This software is instrumental in managing clusters of servers, providing a unified framework that allows for efficient resource management, workload distribution, and high availability.

One of the main features of HP Cluster Software is its ability to deliver high availability through failover mechanisms. In the event of a hardware or software failure, the software automatically shifts workloads from the affected node to a standby node within the cluster, minimizing downtime. This feature is critical for organizations that require continuous access to their data and applications.

Scalability is another significant characteristic of HP Cluster Software. Organizations can easily add or remove nodes from the cluster without disrupting ongoing operations. This flexibility ensures that enterprises can adapt to changing workloads and resource demands efficiently, making it suitable for environments ranging from small businesses to large data centers.

Load balancing is a key technology employed by HP Cluster Software. It intelligently distributes workloads across the available nodes, optimizing resource utilization and ensuring that no single server is overwhelmed. By balancing the load, organizations can achieve better performance and enhance the response times of applications, which are essential for user satisfaction.

HP Cluster Software supports various clustering topologies, including active-active and active-passive configurations. This versatility allows organizations to choose the architecture that best fits their operational requirements. Additionally, the software integrates seamlessly with various HP and third-party hardware and software solutions, thus providing a holistic environment for managing IT resources.

Moreover, HP Cluster Software offers centralized management tools that simplify cluster administration. Administrators can monitor cluster performance, manage workloads, and configure settings all from a single interface. This ease of use reduces the complexity often associated with managing large clusters and empowers IT teams to respond rapidly to issues.

In summary, HP Cluster Software is an essential tool for organizations looking to enhance their IT infrastructure's availability, reliability, and performance. With its failover capabilities, scalability options, load balancing technology, and centralized management features, it stands out as a comprehensive solution for modern computing challenges.
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