[Linux-cluster] FC Fabric and GFS

[isplist at logicore.net]

> I don't know how helpful this will be because I'm not sure exactly what
> you mean by it not seeing your storage (there are many layers you could be 
>referring to),

It seems to be a fabric issue. When I re-connect everything over to regular FC 
hub's, everything's fine, storage shows up on all nodes. When I re-connect the 
nodes to the McData fabric switch, no storage shows up.

> Third, make sure your /etc/lvm/lvm.conf isn't filtering out the device,
> thereby making it invisible as far as lvm is concerned.  A line like this:
> filter = [ "r/sdc/", "r/disk/", "a/.*/" ]
> would make /dev/sdc invisible to lvm.

I have the default which seems to allow everything.
   filter = [ "a/.*/" ]

Other's are commented out.

   # filter = [ "r|/dev/cdrom|" ]
   # filter = [ "a/loop/", "r/.*/" ]
   # filter =[ "a|loop|", "r|/dev/hdc|", "a|/dev/ide|", "r|.*|" ]
   # filter = [ "a|^/dev/hda8$|", "r/.*/" ]
 
> Next, check your /etc/lvm/lvm.conf for locking_type = 2.
> You'll need that to share access to the SAN on the cluster.

Yes, locking_type = 2 is in there.
 
> Next, make sure your clvmd service is started.  If not, do:
> service clvmd start (and perhaps chkconfig clvmd on).

Yes, it's running.

I can't get to any of the following since the storage is not seen;
 
> Next, try a vgchange -aly and vgscan to get clvmd to look again for it,
> pvcreate /dev/sdc
> vgcreate mikes_vg /dev/sdc
> lvcreate -L 39G mikes_vg

yup, I can do all of the above when I can see the storage by using the FC 
hub's but the McData is not allowing the storage to be seen. 
 
> I hope this was helpful.  If not, post which part you're stuck on.

Yes, that's all helpful, a nice order of things to check. I'm looking on the 
RH site trying to find reasons why a fabric switch might make a difference and 
not allow the storage to be seen.

Mike