Expansion order policy in configuration where P-VOL in remote replication shares the same volume with S-VOL in local replication

Expand the volume capacity in the order from the highest layer to the lowest because the expansion order in the local replication is prioritized. Expand the P-VOL capacity in the local replication first, and then the S-VOL capacity in the local replication that shares the same volume with the P-VOL in the remote replication.

For example, when an S-VOL in SI shares the same volume with a P-VOL in TC or UR as shown in the preceding figure, expand the volume capacity in the following order:

1. P-VOL in the SI pair shown as 4 in the figure.
2. S-VOL in the SI pair (P-VOL in the TC or UR pair) shown as 5 in the figure.
3. Volumes in the same layer as the S-VOL in the SI pair.
4. Volumes in the lower layer than the S-VOL in the SI pair.