Cisco ISE does not support VMware snapshots for backing up ISE data because a VMware snapshot saves the status of a VM at a given point in time. In a multi-node Cisco ISE deployment, data in all the nodes are continuously synchronized with current database information. Restoring a snapshot might cause database replication and synchronization issues. Cisco recommends that you use the backup functionality included in Cisco ISE for archival and restoration of data.
Using VMware snapshots or any third-party backup to back up ISE data results in stopping Cisco ISE services. When a backup is initiated by VMware or any third party like CommVault SAN level backup, it quiesces the file system to maintain crash consistency, which causes ISE to freeze. A reboot is required to resume the services on ISE.
Example: VM snapshots, CommVault SAN level backup, etc.