Re: FreeBSD 12.3/13.1 NFS client hang

Hi!

> > Kurt Jaeger <pi@freebsd.org> wrote:
> > > > > I'm having issues with the NFS clients on FreeBSD 12.3 and 13.1

> > > I have it with an 13.0p7 client against an 13.1 server with
> > > a hanging soft-mount (I tried unmount to change it to a hard mount).
[...]
> I take this back. I just did a fairly trivial test of this and it worked.

> Looking at the "ps" output, I don't think your case is a "NFS protocol hang".

Today I upgraded the client to 13.1, and changed the nfs mount
from soft to hard,intr.

nfsstat -M now show this:

# nfsstat -m
<myhost>:/serv on /office/serv
nfsv3,tcp,resvport,nconnect=1,hard,intr,cto,lockd,sec=sys,acdirmin=3,acdirmax=60,acregmin=5,acregmax=60,nametimeo=60,negnametimeo=60,rsize=65536,wsize=65536,readdirsize=65536,readahead=1,wcommitsize=16777216,timeout=120,retrans=2

We use RCS for single files, quite a lot. Sometimes the co -l or the
ci -u would not return and hang as well.

We still have rpc.lockd and rpc.statd running on the server,
are they still used or not ? What happens. 

We also use vi to edit files, and in the past they reliably showed
us when someone on nfsclient A had a file in vi and someone on
nfsclient B tried to edit the same file.

Let's see if the problems re-occurs with hard mounts.

I'll investigate how to move to nfsv4 with a test box as well, if
this helps ?

> I suspect that some process/thread is hung for something non-NFS
> while holding a lock on a NFS vnode. "umount -N" won't know how
> to unhang this process/thread.

> Just a hunch, but I'd suspect one of the threads sleeping on
> "vmopar", although I'm not a vm guy.
> What I don't know how to do is figure out what thread(s) are
> holding vnode locks?

Given that simple NFS mounts and editing with vi on nfs mounts should
be very basic use-cases, it's time to find ways to debug this 8-(

> This also implies that switching from soft->hard won't fix the problem.

Thanks for the encouragement 8-}

> In summary, I don't think your hang is anything like Andreas's, rick

I'll report as soon as I have a another hang.

-- 
pi@FreeBSD.org         +49 171 3101372                  Now what ?