Using block-level backup and Storage Checkpoint


Using block-level backup and Storage Checkpoint
Prev	Appendix E. Alternate methods for synchronizing the Secondary	Next

This method is useful for low bandwidth networks or very large data sets. You can use the block-level backup and Storage Checkpoint method to synchronize the Secondary when a backup of the data is available and a Storage Checkpoint has been started on the Primary. You do not have to use the network to transfer the data. This method does have a risk of SRL overflow.

Make sure that the SRL is large enough to contain all the writes made by the application while synchronization is in progress. If necessary, you can resize the SRL.

Caution:

During the process the Storage Checkpoint will overflow if the SRL fills up. To determine if the Storage Checkpoint has overflowed, issue the vxrvg cplist rvg_name command on the Primary to display the list of valid Storage Checkpoints.

See Example - Synchronizing the Secondary using block-level backup.

To synchronize the Secondary using backup and Primary Storage Checkpoint

Start a Primary Storage Checkpoint using the vxrvg checkstart command:

# vxrvg -g diskgroup -c checkpt_name checkstart  \
     local_rvgname

Perform a block-level backup of the data volumes in the Primary RVG.
End the Storage Checkpoint in the SRL when the backup is complete by using the vxrvg checkend command:
```
# vxrvg -g diskgroup checkend local_rvgname
```
Restore the backup to the Secondary data volumes.
Start replication using the Storage Checkpoint after the restore on the Secondary completes:
```
# vradmin -g diskgroup -c checkpt_name startrep \
 local_rvgname sec_hostname
```
After the RLINKs are attached, the Secondary remains inconsistent until it has received all of the accumulated updates up to the checkend. While the Secondary is inconsistent, the inconsistent flag is set on the Secondary RLINK. After all updates up to the checkend have been received and applied at the Secondary, the inconsistent flag is cleared.

Prev	Up	Next
Example - Synchronizing the Secondary using full synchronization with Storage Checkpoint	Home	Example - Synchronizing the Secondary using block-level backup