[Gluster-devel] gluster questions

[Brent A Nelson]

On Tue, 5 Feb 2008, Matt Paine wrote:

>> -Concerning NFS and tied into the above question: we use it for it's 
>> compatibility with Mac, Linux and Solaris workstations and has worked 
>> fairly well.  We'd like to stick with it.  Would that require running  a 
>> fuse/gluster client on one of the above nodes and re-exporting it as  NFS? 
>> That is the way I seem to understand from my searches on the  mailing 
>> lists.    Or can you directly export a gluster brick via nfs?   And if 
>> running the fuse/gluster client on one of the server nodes w/  exported NFS 
>> is necessary, is this a safe way to do things?
>
> There were problems a while ago about exporting glusterfs volumes as NFS 
> exports, but I believe these problems have now been sorted out (if you use 
> the gluster patched fuse client). I am unable to tell you if Mac and Solaris 
> works with glusterfs exports, but all I can sugest there is to download the 
> source and give it a crack :) Or someone else might be able to jump in with a 
> better answer.
>
>

I've been testing NFS reexport, and it appears that it's working with very 
recent TLAs.  What you need:

1) A custom-compiled FUSE, rather than the FUSE included with the kernel. 
You might as well use the latest GlusterFS-patched version.

2) As stated, a very recent TLA of GlusterFS.  You need patch >=642.

3) Mount your GlusterFS with -d DISABLE on the NFS server, as NFS reexport 
is not currently working with direct-io.

4) Use the fsid=# option on your export in /etc/exports.

That should do it.  It at least seems to work for Solaris and Linux 
clients.  I have still seen an issue on Solaris where an idle bash shell 
cd'ed into the NFS mount may forget its CWD (at least when the GlusterFS 
is an AFR) and am checking to see if actimeo=0 is a useful workaround.  I 
haven't even confirmed if this is a GlusterFS issue, however, and 
everything else seems to work fine.  There used to be other issues, but 
all the ones I observed previously have been fixed, thanks to the diligent 
efforts of the GlusterFS team.

As for GlusterFS mounts directly on Solaris, I haven't tried.  I've been 
watching the mailing lists of FUSE on OpenSolaris (as I'm quite interested 
in this option), and it appears that it may be workable, but they accepted 
a patch a few months ago which broke compatibility with older OpenSolaris 
kernels (such as those found in the OpenSolaris releases, even Solaris 
Express is too old, perhaps especially for Sparc), so you're practically 
forced to work with the latest OpenSolaris (Nevada) code.

Thanks,

Brent Nelson
Director of Computing
UF Physics