Disk device level replication like DRBD, plus a failure control framework like Linux Heartbeat, goes a long way in providing HA cluster for database. Since the replication and failover are at the device level, the solution works with any disk-based system, including databases.
In my experience, failure can be detected in seconds and switched over. Adding a reverse ARP setup to share a virtual IP for the clustering servers, the clients won't even have to talk to a different IP in the case of failover. The only case the clients need to handle is to retry upon failed connection, which they should have handled to deal with the occasional network failure.
In my experience, failure can be detected in seconds and switched over. Adding a reverse ARP setup to share a virtual IP for the clustering servers, the clients won't even have to talk to a different IP in the case of failover. The only case the clients need to handle is to retry upon failed connection, which they should have handled to deal with the occasional network failure.