[Gluster-users] Upgrading gluster installation -- best practices guide?

[Paul]

Hi all,

We run glusterFS in our testing lab (since 2.0rc1). We are currently 
using client-side AFR (mirror) with two server and two clients over GigE.

Testing is going well except one important point: How do you upgrade 
with minimal/zero downtime? Here I have several questions:

1. Is the wire-protocol stable during major releases? Can I mix and 
match all 2.0.x client/servers? If not how do find out which one are 
compatible?

2. Can I export one directory on the servers through multiple instances 
of glusterfsd (running on different ports)? This would allow to run old 
and new version in parallel for a short time and do a test from the client.

3. How do I restart clients without shutting down all services accessing 
the mountpoint? Will glusterfs re-read config via signals (HUP)? Or is 
it OK to kill/restart in one go?

How do YOU handle upgrades, especially wrt downtime and rolling back to 
a known good configuration?


cheers and thanks in advance
  Paul

BTW: I have automated most of compile/install/confgen/start/stop on 
multiple clients/servers via bash/ssh. If someone is interested I could 
share it here.

PS: Sorry to the list moderator, first try with wrong FROM-address