Configure quorum options for a Windows Server Failover Cluster
In this we will learn to configure quorum options for a Windows Server Failover Cluster.
The number of voting elements that must be part of active cluster membership for that cluster to start correctly or continue running determines the quorum for that cluster.
Quorum configuration options
To configure quorum options for a Windows Server Failover Cluster, follow these steps:
- Open the Failover Cluster Manager on one of the cluster nodes.
- In the left pane, select the cluster that you want to configure.
- In the center pane, click the “More Actions” dropdown menu and select “Configure Cluster Quorum Settings”.
- In the “Select Quorum Configuration Option” dialog box, choose the quorum configuration option that you want to use. The available options are:
- Node Majority (recommended for clusters with an odd number of nodes)
- Node and Disk Majority (recommended for clusters with an even number of nodes)
- Node and File Share Majority (recommended for clusters with geographically dispersed nodes)
- No Majority: Disk Only (not recommended for most clusters)
- If you select the “Node and Disk Majority” or “No Majority: Disk Only” options, you will need to select a disk witness to use as the quorum disk. Select the disk that you want to use and click “Next”.
- Review the summary information and click “Next” to confirm the configuration changes.
- After the changes are applied, click “Finish” to exit the wizard.
Note: It’s important to configure the quorum options correctly for your cluster to ensure that it operates reliably and provides high availability for your applications and services.
Dynamic quorum management
Dynamic Quorum Management is a feature of Windows Server Failover Clustering that enables the cluster to automatically adjust the quorum configuration based on the number of available nodes. This feature helps ensure that the cluster can continue to function correctly, even if some nodes become unavailable.
With Dynamic Quorum Management, the cluster can dynamically adjust the quorum configuration by adjusting the vote count of the remaining nodes. For example, if a node fails or is taken offline for maintenance, the cluster will automatically reduce the vote count to reflect the new number of available nodes. If the cluster reaches a point where there are not enough nodes to maintain quorum, it can automatically adjust the quorum configuration by adding a new witness resource, such as a disk or file share, to ensure that quorum is maintained.
Dynamic Quorum Management is particularly useful in larger clusters where nodes may be added or removed frequently, or in clusters where nodes may be geographically dispersed. With this feature enabled, the cluster can automatically adjust to changes in the environment without requiring manual intervention.
To enable Dynamic Quorum Management, you must first ensure that your cluster is running Windows Server 2012 or later. Then, you can enable Dynamic Quorum Management by using the Failover Cluster Manager or PowerShell. Once enabled, the cluster will automatically adjust the quorum configuration as needed, without requiring additional configuration or management.
Windows PowerShell equivalent commands
The following example changes the quorum configuration on cluster CONTOSO-FC1 to a simple node majority configuration with no quorum witness.
PowerShell
Set-ClusterQuorum –Cluster CONTOSO-FC1 -NodeMajority
The following example changes the quorum configuration on the local cluster to a node majority with witness configuration. The disk resource that is Cluster Disk 2 configure as a disk witness.
PowerShell
Set-ClusterQuorum -NodeAndDiskMajority “Cluster Disk 2”
Quorum considerations for disaster recovery configurations
In disaster recovery deployments, this section covers the features and quorum configurations for two multisite cluster topologies. Depending on whether you need automated or manual failover for workloads between locations, the quorum configuration rules vary. Your setup, on the other hand, is often determined by the service level agreements (SLAs) in place in your business to supply and sustain clustered workloads in the case of a site failure or disaster.
Automatic failover
The cluster in this arrangement is made up of two or more sites that may host clustered roles. However, if a site fails, the clustered roles are intended to fail over to the other sites automatically. As a result, cluster quorum setup must be done in such a way that any site can withstand a total site loss.
Manual failover
The cluster comprises of a primary site, SiteA, and a backup (recovery) site, SiteB, in this setup. SiteA is where clustered roles are housed. Because of the cluster quorum arrangement, if all nodes in SiteA fail, the cluster will stop working. In this case, the administrator must fail over the cluster services to SiteB manually and take further actions to restore the cluster.
The following table summarizes considerations and recommendations for this configuration.
DP-300 Exam Practice Questions
Question 1: ABC Corp. has a Windows Server Failover Cluster with three nodes. They want to configure a quorum model that can sustain the loss of one node. Which quorum model should they use?
A. Node Majority
B. Node and Disk Majority
C. Node and File Share Majority
D. No Majority: Disk Only
Answer: B. Node and Disk Majority
Explanation: The Node and Disk Majority quorum model is recommended for clusters with an odd number of nodes. In this scenario, the cluster has three nodes, and with this quorum model, the cluster can sustain the loss of one node. In this model, the quorum is based on a majority of the nodes and a shared disk resource.
Question 2: XYZ Corp. has a Windows Server Failover Cluster with two nodes. They want to configure a quorum model that can sustain the loss of one node. Which quorum model should they use?
A. Node Majority
B. Node and Disk Majority
C. Node and File Share Majority
D. No Majority: Disk Only
Answer: C. Node and File Share Majority
Explanation: The Node and File Share Majority quorum model is recommended for clusters with an even number of nodes. In this scenario, the cluster has two nodes, and with this quorum model, the cluster can sustain the loss of one node. In this model, the quorum is based on a majority of the nodes and a file share witness.
Question 3: PQR Corp. has a Windows Server Failover Cluster with four nodes. They want to configure a quorum model that can sustain the loss of two nodes. Which quorum model should they use?
A. Node Majority
B. Node and Disk Majority
C. Node and File Share Majority
D. No Majority: Disk Only
Answer: A. Node Majority
Explanation: The Node Majority quorum model is recommended for clusters with an odd number of nodes, and it can sustain the loss of (n-1)/2 nodes. In this scenario, the cluster has four nodes, and with this quorum model, the cluster can sustain the loss of two nodes. In this model, the quorum is based on a majority of the nodes.
Question 4: DEF Corp. has a Windows Server Failover Cluster with five nodes. They want to configure a quorum model that can sustain the loss of two nodes. Which quorum model should they use?
A. Node Majority
B. Node and Disk Majority
C. Node and File Share Majority
D. No Majority: Disk Only
Answer: B. Node and Disk Majority
Explanation: The Node and Disk Majority quorum model is recommended for clusters with an odd number of nodes, and it can sustain the loss of (n-1)/2 nodes. In this scenario, the cluster has five nodes, and with this quorum model, the cluster can sustain the loss of two nodes. In this model, the quorum is based on a majority of the nodes and a shared disk resource.
Reference: Microsoft Documentation