Keeping a backup server synced with live server
I am using Zimbra Network Edition 5.04 on a single server with Ubuntu 6.06. I would like to setup a backup server in an other location to implement disaster recovery. I looked at cluster setup, but it requires a shared SAN which I don't have, especially in different locations !
My idea is to have a backup server that I would keep in sync with the live platform by doing incr backup every hours and transferring those to the backup server and replaying them. In case of crash, I would just need to change DNS entries, and the backup server would become live.
For now, I have been able to set up 2 platforms, doing a full backup a week and inc backups every hours and rsyncing the inc backups to the backup server. I have also restored the full backup on the backup server, and been able to replay the inc backups. However, the zmrestore command always restores the account from a full backup then replays the redologs from the inc backups.
Is there a way to only replay the redologs that have not been applied instead of starting with to restore the full backup ? I would then be able to to keep the servers in sync and in case of failure of the live server (complete crash, or network problem, or whatever...), setting the backup server as the main server will only take the time of DNS TTLs, instead of the time of a full restore...
This would also be very useful to lower the downtime when changing for a more powerful server ;)
Of course, any better solution is welcome :)