How does the "retention period" parameter in an ONTAP 9 SnapMirror policy rule work?
Applies to
- ONTAP 9.11.1 and later
- SnapMirror
- DataLock / Immutable Cloud Snapshots
- SnapLock Tamperproof Snapshots
Answer
There are two solutions that utilize the retention-period
parameter in a SnapMirror Policy rule:
- DataLock / Immutable Cloud Snapshots in "vault" type SnapMirror Policies in ONTAP 9.11.1 and later
- In ONTAP 9.11.1 and later, the
retention-period
parameter is used in "vault" type SnapMirror Policy rules by BlueXP Cloud Backup for use with DataLock - DataLock allows Snapshots backed up to the destination object-store to be locked from deletion or modification for a certain period of time
- When used for DataLock, the
retention-period
parameter should never be modified manually - DataLock and its associated settings should always be configured through BlueXP or another licensed partner's backup application
- For more details, see DataLock and Ransomware protection
- SnapLock tamperproof Snapshots in "mirror-vault" type SnapMirror Policies in ONTAP 9.12.1 and later
- In ONTAP 9.12.1 and later, The
retention-period
parameter in a SnapMirror Policy rule is used with the SnapLock Tamperproof Snapshots feature - This parameter is seen when running
snapmirror policy show -instance
and when adding or modifying SnapMirror Policy rules withsnapmirror policy add-rule
andsnapmirror policy modify-rule
for mirror-vault type SnapMirror Policies (Unified Replication)- This parameter is not supported for other SnapMirror policy types for use with SnapLock Tamperprood Snapshots
ClusterA::> snapmirror policy show -policy MirrorAndVault -instance
Vserver: ClusterA
SnapMirror Policy Name: MirrorAndVault
SnapMirror Policy Type: mirror-vault
Policy Owner: cluster-admin
Tries Limit: 8
Transfer Priority: normal
Ignore accesstime Enabled: false
Transfer Restartability: always
Network Compression Enabled: false
Create Snapshot: true
Comment: A unified Asynchronous SnapMirror and SnapVault policy for mirroring the latest active file system and daily and weekly Snapshot copies.
Total Number of Rules: 3
Total Keep: 60
Transfer Schedule Name: -
Throttle: unlimited
Rules:
SnapMirror Label Keep Preserve Warn Schedule Prefix Retention Period
---------------------- ---- -------- ---- -------- ---------- ----------------
sm_created 1 false 0 - - -
daily 7 false 0 - - -
weekly 52 false 0 - - -
- When configuring a mirror-vault type SnapMirror Policy (Unified Replication), this parameter controls how long Snapshots backed up by the SnapMirror relationship are retained and protected against ransomware and malicious admins
- Snapshots with a retention period cannot be deleted by any means until the retention period is met; there are no backdoors
- Retention period takes precedence over the Snapshot's
keep
value in the SnapMirror Policy - For async-mirror type SnapMirror Policies, the retention period of a Snapshot is the same as that of the source-side Snapshot's retention period
Additional Information
- For more information about DataLock, see DataLock and Ransomware protection
- For more information about SnapLock Tamperproof Snapshots, see Tamperproof Snapshot copy locking overview