Zimbra OS Backup Server Questions

[physikal]

I have successfully setup an EC2 server for some redundancy.

My question is, what is the best solution to keep this backup server up to date w/ newly created accounts and emails efficiently. I have run across a few scripts to get it up to date, but how do you keep it up to date?

The most likely scenario initially looks like I will need to use imapsync and synchronize the servers data. But that doesn't seem realistic as you add email accounts to constantly run that and update the script with the list of emails every time you add someone new.

Once you have the servers synced initially, what is the best way to keep them in sync and up to date?

Any advice you can provide would be greatly appreciated.

Thanks!

[p_nyet]

What operating system are used?
My Zimbra running under CentOS 5.3
I'm thingking about clustering using DRBD and HeartBeat
But until now my project isn't finish yet

[physikal]

I am using CentOS 5.3 on both machines.

What is DRDB?

[p_nyet]

DRBD:What is DRBD

DRBD® refers to block devices designed as a building block to form high availability (HA) clusters. This is done by mirroring a whole block device via an assigned network. DRBD can be understood as network based raid-1.

In the illustration above, the two orange boxes represent two servers that form an HA cluster. The boxes contain the usual components of a Linux™ kernel: file system, buffer cache, disk scheduler, disk drivers, TCP/IP stack and network interface card (NIC) driver. The black arrows illustrate the flow of data between these components.

Regards,