Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have planed to use master-slave setup and make nightly backups (just coping data) from slave node to 3rd node.

As I understand in master-slave mode it is impossible to read data from slave node? So the question is... what will happened if I will use master-master setup without cluster fs, and will use one of master just as read-only to make backups of it and writes will occur only to second master.

On top of setup will be NFS exports and iSCSI.

Will it work? Maybe there will be some problems...?

share|improve this question
If you are not using a cluster fs you can read from the secondary server, but only from drdb and not mount a filesystem, so you could or example use dd to copy the bits but that's probably not what you want. It would be probably easier to just create a master/master setup and write only to one node, but use the second node for backups. – Jure1873 Nov 22 '12 at 17:21

For a simple task like backup, I recomment csync2.

Csync2 is a cluster synchronization tool. It can be used to keep files on
multiple hosts in a cluster in sync. Csync2 can handle complex setups with
much more than just 2 hosts, handle file deletions and can detect conflicts.
share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.