Looking for real-time replication software 1

[sbrews]

I am looking for some software that will allow me to duplicate a mount from one system to another system.

The software should meet these requirements:

Will work with Red Hat Enterprise Linux 6.5 (and optionally RHEL 5.10)
Will duplicate the change - in real time - on the remote system
Will allow the remote system to have that file system mounted - ie data can be read on both systems.
Note that each system has its own storage - shared storage (ie san) is not an option.

I am aware of and have used rsync, but that is not real-time and depending on the amount of data - it can be several hours to complete the replication.

Does such a thing exist for Linux?

 

[SamBones]

Have you considered NFS? One system owns the volume, the other mounts it, so it's the same file system being accessed by both systems.

The Cons are, 1) that if the system that's sharing the filesystem goes down, it's all down, and 2) access to the file system by the remote system is slower (network speed vs native disk speed). The Pro is that both systems are working off of the same exact file system, not copies.

 

[SamBones]

Oh, and additional Pro, it's free. The capabilities are already there in RedHat. That means you can try it without incurring any expense.

 

[sbrews]

I have considered NFS, but that doesnt satisfy the replicated data. Having the data available via NFS wouldnt work if the source server were unavailable. The data needs to be duplicated.

 

[BIS]

Check out Heartbeat

 

[nychris]

DRBD will do exactly as you are asking. It's like having a RAID 1 mirror over the network.

http://www.drbd.org/

 

[sbrews]

After looking at several things, Doubletake and drbd seem like the most viable options and satisfy our requirements. Now to do an actual side-by-side test to see which is the better option.