In order to maintain consistency and stability, only one cluster operation can run at a time. To ensure this, SPP locks the cluster while a cluster operation is running, such as enroll, unjoin, failover, patch, reset, session module join, update IP, and audit log maintenance. While the cluster is locked, changes to the cluster configuration are not allowed until the operation completes.

The lock notification displays as follows:

• web client: The Appliance State will show a red lock icon ().

You should never cancel the cluster lock for an SPP unjoin, failover, cluster reset, restore, patch, or IP address update. Other considerations:

• If a SPP join (enroll) is taking a long time, you may cancel it during the streaming audit data step.
• If a patch distribution is taking a long time, you may cancel it and upload the patch to the replicas directly.
• If an audit log synchronize operation is taking a long time, or you have reason to believe it will not complete due to a down appliance in the cluster, you may cancel it. Canceling this operation requires monitoring as detailed in Cancel Audit Log Maintenance from the Audit Log Maintenance page.
  

• If an audit log archive or purge operation is taking a long time, or you have reason to believe it will not complete due to a down appliance in the cluster, you may cancel it. Canceling this operation requires monitoring as detailed in Cancel Audit Log Maintenance from the Audit Log Maintenance page.

To unlock a locked cluster

1. Go to Cluster Management:
   • web client: Navigate to Cluster > Cluster Management.
2. Click the lock icon in the upper right corner of the warning banner.

3. In the Unlock Cluster confirmation dialog, enter Unlock Cluster and click OK.

   This will release the cluster lock that was placed on all of the appliances in the cluster and close the operation.