Date: Tue, 18 Mar 2003 17:00:43 -0800 From: Steve Sizemore <steve@ls.berkeley.edu> To: Terry Lambert <tlambert2@mindspring.com> Cc: current@freebsd.org Subject: Re: NFS file unlocking problem Message-ID: <20030319010042.GD875@math.berkeley.edu> In-Reply-To: <3E77A275.4F4B5B1F@mindspring.com> References: <Pine.LNX.4.44.0303171255310.15683-100000@mail.allcaps.org> <3E768C47.229C1DF0@mindspring.com> <20030318065716.GB99408@math.berkeley.edu> <3E76CC9A.BBAAED4A@mindspring.com> <20030318172237.GA320@math.berkeley.edu> <3E77A275.4F4B5B1F@mindspring.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, Mar 18, 2003 at 02:49:25PM -0800, Terry Lambert wrote:
> Steve Sizemore wrote:
> > I don't see now it could be "inter-program", since I've gone to great
> > lengths to simplify it to a single program failing on a brand new file.
>
> Is the file ever open by a program on the NFS server itself?
Not explicitly by me or anything that I'm aware of. The only way that
it could be opened is if some daemon is sitting there waiting for a
new file to appear and then opening it. Not likely. Even if it were,
wouldn't the problem then also be seen when using a FreeBSD nfs
client?
>
> > Oh, so that's what that meant. :-) But (see above) it's pretty clear
> > to me that nothing else could have it locked.
>
> Then you aren't getting the error. 8-) 8-) 8-).
But you're assuming that locking is working properly, and the only
reason that it could hang is that there is a legitimate lock on the
file.
> > No, but this might be an important clue. The FreeBSD host has multiple
> > (2) A Records in the DNS. In fact, I think that when it last worked,
> > it had only a single A Record.
>
> Well, try undoing that change. I don't think that's it, though,
> but it gives you a lever to pull.
Not such an easy lever. I can't really undo that, because mail virtual
hosting requires it.
>
> > > If so, try:
> > >
> > > sysctl -w net.inet.ip.check_interface=0
> >
> > What does this do, just turn off checking? Can I do this on the
> > running system, or do I need to put it into sysctl.conf and reboot?
> > (BTW, from the man page -
> > "The -w option has been deprecated and is silently ignored.")
>
> Use it on a running system. Ignore the warning.
You didn't tell me what it does, but I very trustingly
did it anyway. No effect.
Oh, and I built and ran the locktest.c program you sent me. On a
local file, it returns instantly the message "There is no lock that
would block you!" I've run it three times on the NFS mounted FS and
it has "hung" each time, long enough that I've gone away to do other
things, but when I return, the program has terminated, and I get
the same message. Right now I'm running under "time", so I'll see
how long it actually took. I don't think that the values I enter
for lock start, lock length, and whence are important. (Are they?)
After about 40 minutes, the locktest running under time still hadn't
returned, so I interrupted it. At least it died on interrupt, and
didn't force me to kill the session.
I think I'm going to have to build another 5.0 system on this same
subnet so I can use it for testing.
Steve
--
Steve Sizemore <steve@ls.berkeley.edu>, (510) 642-8570
Unix System Manager
Dept. of Mathematics and College of Letters and Science
University of California, Berkeley
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030319010042.GD875>