When the following conditions apply, a ShadowImage for Mainframe pair is suspended, and the status of the pair is changed to PSUE/SUSPER:
- The storage system detects an error condition related to an update copy operation.
- The storage system cannot keep the pair mirrored.
At this time, write I/Os to the P-VOL continue and all tracks of the P-VOL are saved as differential data. When the pair is resynchronized, the pair status changes to Resync/PENDING, and the entire P-VOL is copied to the S-VOL. For a split pair (pairsplit -S), resynchronization is completed in a short time, but for a suspended pair it takes the same amount of time to be resynchronized as the initial copy operation.
You can force the pair into the suspended state (PSUE). This can be used to interrupt the copy process but is normally not used.
Maintenance on LDEVs used by ShadowImage for Mainframe pairs is restricted. However, for LDEVs used only by pairs in the PSUE state, maintenance blocking, formatting, and recovery can be performed.
To perform this task in CCI, use the pairsplit -E command.
This task cannot be performed by using BCM.