[Gluster-users] Gluster upgrade planning

[Jamie Lawrence]

Hello all,

We are working on an upgrade plan that touches a number of things, one of them being our Gluster setup. I wanted to throw some of this out and see if anyone sees any glaring problems with it. One of our constraints  is that our current Gluster installation is production and cannot fully go down. (Remounts, etc. are fine.)

We currently are running 3.6.2, and have approximately 48TB (available) across 10 volumes on six hosts. Most volumes are small distribute-replicate 2x2; one is about half of the available storage and is replicate, 1x2. We use Gluster clients and NFS on some volumes. The storage network is all 10G, the rest of the hardware is relatively young Dell commodity kit.


We will be adding a couple NAS devices (in different locations) with about 100TB (raw) additional each. We geo-replicate for DR. We’ll be physically installing those first, so that there’s slack space for us to rearrange/reconfigure as needed during this process. This will run ZFS on ubuntu.

The plan, in loose terms, will be to add  machines (an arbiter, NASes and machines to front the NASes) to the cluster, restructure the volumes/mountpoints to be somewhat more aligned with what we currently do, upgrade/perhaps switch distros, upgrade Gluster, and revamp monitoring. Not in that order.

Questions:

 - Is anyone currently running Gluster on Debian or Ubuntu in production? We would prefer to get off RHEL-flavored hosts (currently Centos 7), thus I’m hoping I’m wrong, but I’ve seen little evidence that trying this for production would be a safe endeavor.[1]

- Alongside of this (meaning, as part of the overall plan, but not necessarily as an integral part of upgrading Gluster), we’re installing oVirt to take the place of multiple xen hosts. I know the two projects have been adding all sorts of pretty integration between the two projects, but am unclear on what exactly the payoff is for managing Gluster via oVirt for people happy with command line management. Anyone have any thoughts there?

 - Since these are all 2x2 or 1x2, I know we need to add at least arbiter nodes. Is there anything amiss with the idea of adding a single machine to arbitrate all of those? 

 In general, does anyone see any problems with this plan?

Thanks in advance for any thoughts.

-j

[1] I’m aware that oVirt is also RHEL-oriented.