Follow these best practices when using snapshots in the vSphere environment:
- Do not use snapshots as backups.
The snapshot file is only a change log of the original virtual disk, it creates a place holder disk, virtual_machine-00000x-delta.vmdk, to store data changes since the time the snapshot was created. If the base disks are deleted, the snapshot files are not sufficient to restore a virtual machine.
- Maximum of 32 snapshots are supported in a chain. However, for a better performance use only 2 to 3 snapshots.
- Do not use a single snapshot for more than 72 hours.
The snapshot file continues to grow in size when it is retained for a longer period. This can cause the snapshot storage location to run out of space and impact the system performance.
- When using a third-party backup software, ensure that snapshots are deleted after a successful backup.
Note: Snapshots taken by third party software (through API) may not appear in the Snapshot Manager. Routinely check for snapshots through the command-line.
- Ensure that there are no snapshots before:
- Performing Storage vMotion in vSphere 4.x and earlier environments.
Note: vSphere 5.0 and later support Storage vMotion with snapshots on a virtual machine.
- Increasing the virtual machine disk size or virtual RDM.
Increasing the disk size when snapshots are still available can corrupt snapshots and result in data loss.