This topic describes how to force a Windows Server
Failover Clustering (WSFC) cluster node to start without a quorum. This
may be required in disaster recovery and multi-subnet scenarios to
recover data and fully re-establish high-availability for Always On
availability groups and SQL Server Failover Cluster Instances.
- Before you start: Recommendations, Security
- To force a cluster to start without a quorum using: Using Failover Cluster Manager, Using Powershell, Using Net.exe
- Follow up: Follow Up: After Forcing Cluster to Start without a Quorum
Before You Start
Recommendations
Except where explicitly directed, the procedures in this topic should work if you execute them from any node in the WSFC cluster. However, you may obtain better results, and avoid networking issues, by executing these steps from the node that you intend to force to start without a quorum.Security
The user must be a domain account that is member of the local Administrators group on each node of the WSFC cluster.Using Failover Cluster Manager
To force a cluster to start without a quorum
- Open a Failover Cluster Manager and connect to the desired cluster node to force online.
- In the Actions pane, click Force Cluster Start, and then click Yes - Force my cluster to start.
- In the left pane, in the Failover Cluster Manager tree, click the cluster name.
- In the summary pane, confirm that the current Quorum Configuration value is: Warning: Cluster is running in ForceQuorum state.
Using Powershell
To force a cluster to start without a quorum
- Start an elevated Windows PowerShell via Run as Administrator.
- Import the
FailoverClusters
module to enable cluster commandlets.
- Use
Stop-ClusterNode
to make sure that the cluster service is stopped.
- Use
Start-ClusterNode
with-FixQuorum
to force the cluster service to start.
- Use
Get-ClusterNode
with-Propery NodeWieght = 1
to set the value the guarantees that the node is a voting member of the quorum.
- Output the cluster node properties in a readable format.
Example (Powershell)
The following example forces the Always OnSrv02 node cluster service to start without a quorum, sets theNodeWeight = 1
, and then enumerates cluster node status from the newly forced node.
PowerShell
Import-Module FailoverClusters
$node = "Always OnSrv02"
Stop-ClusterNode -Name $node
Start-ClusterNode -Name $node -FixQuorum
(Get-ClusterNode $node).NodeWeight = 1
$nodes = Get-ClusterNode -Cluster $node
$nodes | Format-Table -property NodeName, State, NodeWeight
Using Net.exe
To force a cluster to start without a quorum
- Use Remote Desktop to connect to the desired cluster node to force online.
- Start an elevated Command Prompt via Run as Administrator.
- Use net.exe to make sure that the local cluster service is stopped.
- Use net.exe with
/forcequorum
to force the local cluster service to start.
Example (Net.exe)
The following example forces a node cluster service to start without a quorum, sets theNodeWeight = 1
, and then enumerates cluster node status from the newly forced node.
ms-dos
net.exe stop clussvc
net.exe start clussvc /forcequorum
Follow Up: After Forcing Cluster to Start without a Quorum
- You must re-evaluate and reconfigure NodeWeight values to
correctly construct a new quorum before bringing other nodes back
online. Otherwise, the cluster may go back offline again.
For more information, see WSFC Quorum Modes and Voting Configuration (SQL Server).
- The procedures in this topic are only one step in bringing the
WSFC cluster back online if an un-planned quorum failure were to occur.
You may also want to take additional steps to prevent other WSFC
cluster nodes from interfering with the new quorum configuration.
- Other SQL Server features such as Always On availability groups, database mirroring, and log shipping may also require subsequent actions to recover data and to fully re-establish high-availability.For more information:
Perform a Forced Manual Failover of an Availability Group (SQL Server)
Force Service in a Database Mirroring Session (Transact-SQL)
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