Resynchronization – HP 3PAR Operating System Software User Manual
Page 125
4.
Saves the active snapshot, which enables HP 3PAR Remote Copy to perform a fast
resynchronization later (
).
Figure 39 Full Synchronization Using Primary Volume Snapshots (Asynchronous Periodic Mode)
Resynchronization
Remote copy performs a resynchronization if both of these conditions are met:
•
The primary volume was previously synchronized.
•
A valid (up-to-date) resynchronization snapshot exists.
When performing a resynchronization (see (
), HP 3PAR Remote Copy:
1.
Takes a snapshot of the data in the primary volume and takes a snapshot of the data in the
secondary volume.
2.
Compares the most recent resynchronization snapshot and the current synchronization snapshot
and determines the changes that occurred between the creation of each snapshot.
3.
Transmits only the changes between snapshots to the secondary volume.
4.
After synchronization is completed, deletes the snapshots created on the backup system.
The base volumes now represent a valid point-in-time copy.
5.
Saves the newer snapshot for a future resynchronization.
CAUTION:
Because remote copy uses multiple snapshots during resynchronization, you must
ensure that the space available to virtual volumes is adequate. For more information, see
“Virtual Volumes and CPGs” (page 108)
Synchronization
125