Remote deferred deletion

The remote bridge could be registered with remote deferred deletion enabled. This feature will enable a user in Cluster A to unexport and set remote snapshots for deferred deletion in Cluster B.

Note

This feature is available for both multi-cluster and multi-site configurations. Note that the minimumDeleteDelay flag (see Minimum deletion delay) is per bridge, not per location. Thus, all bridges to a remote location should be (re)registered with the setting.

Example

Here is an example for the case without deferred deletion enabled:

  • Cluster_A and Cluster_B are two StorPool clusters in locations A and B connected with a bridge.

  • A volume named volume1 in Cluster_A has two backup snapshots in Cluster_B called volume1@281 and volume1@294.

digraph G { graph [nodesep=0.5, ranksep=1] rankdir=LR; compound=true; image=svg; subgraph cluster_a { style=filled; color=lightgrey; node [ style=filled, color=white, shape=square, label="Bridge A", ]; bridge0; node [ shape=rectangle, ] v1 [label=volume1] {rank=same; bridge0 v1} label = "Cluster A"; } subgraph cluster_b { style=filled; color=grey; node [ style=filled, color=white, shape=square, label="Bridge B" ]; bridge1; node [ shape=circle, ] v1s [label="volume1@281"] v2s [label="volume1@294"] v1s -> v2s [dir=back] {rank=same; bridge1 v1s v2s} label = "Cluster B"; } bridge0 -> bridge1 [color="red", lhead=cluster_b, ltail=cluster_a]; bridge1 -> bridge0 [color="blue", lhead=cluster_a, ltail=cluster_b]; }

The remote snapshots could be unexported from Cluster_A with the deleteAfter flag, but it will be silently ignored in Cluster_B.

Procedure

To enable remote deferred deletion, the following steps would have to be completed in the remote bridge for Cluster_A:

  1. The bridge in Cluster_A should be registered with minimumDeleteDelay in Cluster_B.

  2. Deferred snapshot deletion should be enabled in Cluster_B; for details, see Management configuration.

This will enable setting up the deleteAfter parameter on an unexport operation in Cluster_B initiated from Cluster_A.

With the above example volume and remote snapshots, a user in Cluster_A could unexport the volume1@294 snapshot and set its deleteAfter flag to 7 days from the unexport with:

user@hostA # storpool snapshot remote location_b locationAId.aId.q unexport deleteAfter 7d
OK

After the completion of this operation the following events will occur:

  1. The volume1@294 snapshot will immediately stop being visible in Cluster_A.

  2. The snapshot will get a deleteAfter flag with timestamp a week from the time of the unexport call.

  3. A week later the snapshot will be deleted, however only if deferred snapshot deletion is still turned on.