Originally Posted by cormanstnl
Actually, we have a RHEL 4 with customized kernel for XFS fs support.
we must change the hardware of server and install a new server.
the server make PDC, file/print server (Samba) with ldap backend.
For prepare this migration, I look for a other filesystem than XFS because RH not support XFS and some times we have problem with some limitations of XFS (ex : 25 ACL entries) and also because we want to make this server in a high avaibility context.
For that I try to find a FS which permit to have a data replication over ethernet between to servers.
I know that GNBD or DRBD can make that, but each server will be connected to her SAN (2 servers, two SAN) with LVM.
Now, I want to know what is the best FS or system which permit to have data mirroring between to server and support LVM. The configuration can be master -> slave or master <-> master.
I looked GFS and GNBD but the GNBD and lvm compatibility is not sure and I don't want have problem
with data corruption.
There was some days ago a thread on the gfs-mailing list that nobody yet tried GFS with gnbd and data replication.
But the outcome was that it might
work with gndb and cmirror as part of the devicemapper.
But neither ways I would be extremely concerned about performance and synchronisations of i/os.
When using DRBD you end up in the same dilema as before. IMHO DRBD is not offically part of RHEL4/5 and therefor not supportet. Besides you would need DRBD/GNBD/cLVM/GFS for GFS or DRBD/ext3 for ext3. I won't use it with GFS.
BTW: Basically this is independent from the filesystem. So you are more or less free to use any filesystem on top.
Advantage for GFS is that it is a clusterfilesystem that you can concurrently mount and access on all nodes belonging to a cluster and build up a active/active Samba cluster. So no double mounts or stuck unmounts when doing the failover.
I would extremly advice you to do a lot of testing and think about the possibly of other ways to do the replication (or leave it because of complexity and performance) or use the storagesystem functionality if available.
Have fun trying