Re: [tlug] Help with fsck and ocfs2 (or even ext4?)...

[Christian Horn <chorn@example.com>]

Hoi,

On Mon, Sep 27, 2021 at 11:06:24AM +0800, Raymond Wan wrote:
> On 20/9/2021 6:12 am, Christian Horn wrote:
> > On Mon, Sep 20, 2021 at 01:21:17AM +0800, Raymond Wan wrote:

> [..]
> So, would this work, then?  What if I picked a server on my cluster of
> 5 servers.  Let's say node1.  I format the SAN as an ext4 and the
> node1 mounts this SAN.  But then, it exports it to the other servers
> in its /etc/exports file.  And the other nodes mounts it as if it
> belonged to node1 using NFS.  Does this effectively mean that node1
> becomes this SAN's "manager"?

Sounds good.  If that first node has an issue like broken hard-
ware which can not be fixed quickly, you could make one of the other
nodes the nfs server.

> I think I would like to avoid either OCFS2 or GFS2, if I can.  I'm
> sure it would be the best solution (somehow...).  Perhaps it would
> distribute the workload of locking equally across all servers instead
> of giving the burden all to node1.  But it seems difficult [to me] and
> more trouble than it's worth [so far].

NFS without an HA-cluster here would require you to manually make a
different node the NFS-server.  With OCFS2/GFS2, ideally the client
would not notice if one of the servers goes down.

> Thank you for this list!  I really appreciate how you laid it out for
> me in such a clear way.  I actually saw both e-mails before I started
> writing my reply.  Guess I wanted to make sure I understood what was
> being said.
> In essence, what I said at the beginning of this e-mail is option (a)
> exactly, right?  Perhaps I should try that.

Yes, it's a).

> Thank you for all your help!  Really lost here...would have liked to
> be looking after this SAN with a team so that we can discuss options,
> but it's just me.

NP.  I'ts a niche topic, I just happen to know something about that
as we offer GFS2 support and work on the code.

> http://www.linux-kongress.org/2010/slides/gfs2ocfs2-seidel.pdf 

That's a nice piece
(full disclosure: I know Udo, the author)

Chris