Appsync: Unity snapshots are not deleted from array even though it is expired from AppSync GUI.
Summary: AppSync snapshots are not expired from array as per the rotation policy.
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Symptoms
No Change
The AppSync service plan completes successfully, snapshots are expired from AppSync GUI as per the rotation policy, but intermittently leaves the snapshots not deleted on the Array.
The AppSync service plan completes successfully, snapshots are expired from AppSync GUI as per the rotation policy, but intermittently leaves the snapshots not deleted on the Array.
Cause
The scenario in which this issue has been encountered is for a DataStore protection in a distributed VPLEX/Unity environment. (Two VPLEX clusters + two Unity arrays respectively).
There are two Service Plans:
ServicePlan1 uses VPLEX1 cluster and Unity 1 array as preferred for snaps.
ServicePlan2 uses VPLEX2 cluster and Unity 2 array as preferred for snaps.
Schedule ServicePlan1 and ServicePlan2 to run one after the other with a fixed rotation count.
When snapshots are created from both service plans, the same SnapIDs on two distinct arrays can be generated.
The SnapID is however used by AppSync to uniquely identify snapshots internally by AppSync. After creating a snap, AppSync uses the SnapID while making some of the internal Database queries and to persisting VPLEX entities and Unity array snaps relations.
In this situation where two copies on separate arrays have the same SnapID, AppSync may attempt and to expire the copy for the wrong ServicePlan and subsequently leave the copy that was to be expired on the array.
As a result, wherever there is non-unique SnapID, some snapshots are left behind on the array even after expiry of the copy.
There are two Service Plans:
ServicePlan1 uses VPLEX1 cluster and Unity 1 array as preferred for snaps.
ServicePlan2 uses VPLEX2 cluster and Unity 2 array as preferred for snaps.
Schedule ServicePlan1 and ServicePlan2 to run one after the other with a fixed rotation count.
When snapshots are created from both service plans, the same SnapIDs on two distinct arrays can be generated.
The SnapID is however used by AppSync to uniquely identify snapshots internally by AppSync. After creating a snap, AppSync uses the SnapID while making some of the internal Database queries and to persisting VPLEX entities and Unity array snaps relations.
In this situation where two copies on separate arrays have the same SnapID, AppSync may attempt and to expire the copy for the wrong ServicePlan and subsequently leave the copy that was to be expired on the array.
As a result, wherever there is non-unique SnapID, some snapshots are left behind on the array even after expiry of the copy.
Resolution
A HotFix exists for AppSync 3.5.0 that allows the SnapID along with the ArrayID to be used to reference AppSync Unity Snap objects.
Note this article when opening a service request.
The Hotfix will prevent this issue from happening for newly created snapshots only. Existing snapshots that have been left behind on the array need to be removed manually using the arrays native tools. Refer to the appropriate documentation for the array for instructions.
The fix is expected to be included in the version of AppSync following 3.7.
Refer to the release notes of the subsequent versions beyond 3.5.0 to determine if the fix is included in the version you are running.
Note this article when opening a service request.
The Hotfix will prevent this issue from happening for newly created snapshots only. Existing snapshots that have been left behind on the array need to be removed manually using the arrays native tools. Refer to the appropriate documentation for the array for instructions.
The fix is expected to be included in the version of AppSync following 3.7.
Refer to the release notes of the subsequent versions beyond 3.5.0 to determine if the fix is included in the version you are running.
Additional Information
The HotFix cannot resolve the expiry issue for the existing copies. (This is because for the existing copies, their SnapIDs and relations are already persisted in the AppSync Database and cannot be changed).
So, the impact of the HotFix will be seen only for the rotation of the copies which are effectively created after applying the HotFix.
So, the impact of the HotFix will be seen only for the rotation of the copies which are effectively created after applying the HotFix.
Affected Products
AppSyncProducts
AppSyncArticle Properties
Article Number: 000167906
Article Type: Solution
Last Modified: 18 Sept 2025
Version: 3
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