This ensures that more than 50% of the nodes will have an
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
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
•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 The file share witness feature prevents the cluster node that contains outdated cluster state information from running the cluster.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