GFS2 or any other filesystems being replicated are not aware at all of the block replication taking place in the storage layer. This is entirely transparent to the OS and filesystems clustered or not. Replication happens entirely in the array/SAN layer and the servers are not involved at all.
So, there is nothing for Red Hat to support or not support – they just do not see it. Nor do they have any ability to see it even if they wanted. Very often the array ports for replication are on separate ports and in separate FC zones.
Storage replication may have some performance impact, but this just looks like slower disks. GFS2 does not have any specific numerical requirements for IO rate, bandwidth and latency.
Could you quote the Red Hat KB – what exactly does it say and in what context?
Hi GFS2 gurus,
I am planning to setup 2 x 2 nodes clusters in our environment with using emc storage to build cluster shared filesytems (GFS2).
PROD: 2 nodes ( cluster 1)
DR: 2 nodes ( cluster 2).
as below shows:
My question is that GFS2 supports SRDF ?? looking at KB in redhat site, it only says that GFS2 does not support using asynchronous or active/passive array based replication. but it seems like does not apply for SRDF.
if anyone has done this before, appreciate you can give some ideas.