HP 3PAR Remote Copy Software - Manual (Page 45)

2.29 Remote Copy Operation
InForm OS Version 2.3.1 Remote Copy User’s Guide
2.9.4 Manual Resynchronization
Additional manual resynchronizations might be initiated for asynchronous periodic or
synchronous mode volume groups using the syncrcopy command. When using this
command, only the changes to the primary volume group after the last resynchronization
point are sent over the network to the backup storage server. Use the syncrcopy -ovrd
command to force a synchronous mode volume group to synchronize. This causes a full
synchronization.
2.9.5 Concurrent Synchronization Limits
To limit the performance impact of Remote Copy on the rest of the InServ Storage Server, the
number of volumes that are concurrently synchronizing is limited to 20 volumes. This limit is
not user-configurable and applies to the initial synchronization as well as subsequent
resynchronizations for the synchronous as well as the asynchronous periodic groups. See
Synchronous Mode on page 2.23 and Asynchronous Periodic Mode on page 2.24 for additional
information about synchronous and asynchronous periodic groups.
For example, if there are 30 volumes in the asynchronous periodic mode that are being
resynchronized, you might notice that 10 volumes do not start synchronizing until some of the
first 20 complete. This can be seen by monitoring the SyncStatus column of the showrcopy
command output (see showrcopy on page B.57 for example output).
To ensure volume group consistency, all snapshots for the asynchronous periodic group are
maintained on the secondary server until all of the volumes in that group have completed
synchronization.
NOTE: To schedule a synchronization to take place at a particular time (for
example, 12:00 pm daily), use a host-based script and manual resynchronization.
NOTE: For complete details on the showrcopy command, including valid
synchronization, link, and group states, see showrcopy on page B.57.