Re: two /net paths to the same local mount?

[Ian Kent <raven@themaw.net>]

On Wed, 2010-06-30 at 07:57 -0700, Chris Quenelle wrote:
> On Wednesday June 30    6:12AM, Ian Kent wrote:
> > On Tue, 2010-06-29 at 09:14 -0700, Chris Quenelle wrote:
> >> Ian,
> >>
> >> Thanks again for your help.
> >> I have syslog-ng installed, and I can't figure out how to tell
> >> if "daemon.*" is being sent somewhere or not.  "daemon" doesn't
> >> appear anywhere in /etc/syslog-ng/syslog-ng.conf
> >
> > Well, you need to consult the man page for the configuration file then
> > don't you.
> 
> Sorry for sounding lazy there.  I've never used syslog-ng before, and
> I read the man page for a while without figuring how the old style
> of names/categories mapped to the new system.  I'll continue to fiddle
> around and see if I can find out what's going on.
> 
> Thanks for helping me get started with the debugging output.
> 
> My autofs map looks like this:
> % ypcat -k auto.master | grep /net
> /net -hosts -intr,nosuid,retrans=10,retry=3,nobrowse
> 
> But I'm not sure that helps.

Is automount crashing, ie. does it show up in a ps listing after you see
it hang?

> 
> --chris
> 
> 
> 
> >
> > For me, when syslog was in use and now with rsyslog, I just add a new
> > line to send all the facility daemon output to a log file.
> >
> > I add the line:
> >
> > daemon.*                                /var/log/debug
> >
> > to the configuration and then
> >
> > touch /var/log/debug
> >
> > and finally restart logging service.
> >
> > You probably should post your autofs maps as well.
> >
> >> But when I grep /var/log/messages I see:
> >>
> >> % grep automount messages
> >> Jun 29 02:41:14 carabas automount[11786]: lookup_mount: lookup(yp): key "Codemgr_wsdata" not found in map
> >> Jun 29 02:41:14 carabas automount[11786]: lookup_mount: lookup(yp): key "Codemgr_wsdata" not found in map
> >> Jun 29 03:17:45 carabas automount[11786]: lookup_mount: lookup(yp): key "opt" not found in map
> >> Jun 29 03:24:27 carabas automount[11786]: lookup_mount: lookup(yp): key "Codemgr_wsdata" not found in map
> >> Jun 29 03:24:27 carabas automount[11786]: lookup_mount: lookup(yp): key "Codemgr_wsdata" not found in map
> >> Jun 29 09:04:46 carabas automount[11786]: Debug logging set for /net
> >> Jun 29 09:09:22 carabas automount[11786]: get_pkt: message pending on control fifo.
> >> Jun 29 09:09:22 carabas automount[11786]: Basic logging set for /net
> >>
> >> I didn't get the get_pkg message until I turned off debug logging.
> >>
> >> While logging was set to debug, I tried the hanging ls command again, and
> >> I also tried listing a different file system that was actually remote.
> >> I didn't see any log messages for those operations.
> >>
> >> Notes:
> >>
> >> 1. /etc/host.conf says only:
> >>        order hosts, bind
> >>        multi on
> >>
> >> 2. No mount.nfs processes are running when the ls command hangs
> >>     on the local mount.
> >>
> >>
> >> Ian Kent wrote:
> >>> On Wed, 2010-06-23 at 11:32 -0700, Chris Quenelle wrote:
> >>>> Thanks for your time guys!
> >>>>
> >>>> It turns out it's not a general bug.  I was just applying
> >>>> a pessimistic interpretation without checking.
> >>>>
> >>>> After more testing, it turns out it's just problem
> >>>> on one machine, for two mount points under one
> >>>> host alias.
> >>>>
> >>>> I'm interested in knowing more about how I could
> >>>> debug the situation without just rebooting and
> >>>> hoping it doesn't happen again.
> >>>>
> >>>> Here's my scenario:
> >>>>
> >>>> I have three exported filesystems.
> >>>> I can use three host aliases to refer to my own machine.
> >>>> (carabas, carabas.sfbay, carabas.sfbay.sun.com)
> >>>>
> >>>> /etc/hosts says:
> >>>> [IP addr]     carabas.sfbay.sun.com carabas
> >>>>
> >>>>
> >>>> All filesystems work under all /net/foo aliases
> >>>> except two of them hang when accessed via one
> >>>> of the host aliases.
> >>>
> >>> Are you sure the address lookup is returning what you think it does?
> >>> What's in /etc/host.conf?
> >>>
> >>>> % showmount -e localhost
> >>>> Export list for localhost:
> >>>> /export/home3 *
> >>>> /export/home2 *
> >>>> /export/home1 *
> >>>>
> >>>>
> >>>> % df -kl
> >>>> Filesystem           1K-blocks      Used Available Use% Mounted on
> >>>> /dev/sda2             69575344   3408900  66166444   5% /
> >>>> udev                   8222568       148   8222420   1% /dev
> >>>> /dev/sdb1             71671728  26507132  45164596  37% /export/home1
> >>>> /dev/sdc1             71671728   8545196  63126532  12% /export/home2
> >>>> /dev/sdd1             71671728   5375672  66296056   8% /export/home3
> >>>> /export/home1         71671728  26507128  45164600  37% /net/carabas/export/home1
> >>>> /export/home2         71671728   8545196  63126532  12% /net/carabas.sfbay/export/home2
> >>>> /export/home1         71671728  26507128  45164600  37% /net/carabas.sfbay/export/home1
> >>>> /export/home3         71671728   5375672  66296056   8% /net/carabas.sfbay/export/home3
> >>>> /export/home1         71671728  26507128  45164600  37% /net/carabas.sfbay.sun.com/export/home1
> >>>> /export/home2         71671728   8545196  63126532  12% /net/carabas.sfbay.sun.com/export/home2
> >>>> /export/home3         71671728   5375672  66296056   8% /net/carabas.sfbay.sun.com/export/home3
> >>>>
> >>>>
> >>>> % strace ls /net/carabas/export/home2
> >>>> ...
> >>>> ...
> >>>> mmap(NULL, 217016, PROT_READ, MAP_SHARED, 4, 0) = 0x2b2388370000
> >>>> close(4)                                = 0
> >>>> close(3)                                = 0
> >>>> open("/net/carabas/export/home2", O_RDONLY|O_NONBLOCK|O_DIRECTORY<unfinished ...>
> >>>
> >>> What does a ps listing give you when it is blocked?
> >>> Any mount.nfs processes?
> >>>
> >>> That's sign that automount thinks that the mount isn't local and is
> >>> probably trying to mount from a possibly non-existent ip address.
> >>>
> >>>> I hit ctrl-C when the ls command hangs.  Above is the tail of the strace output.
> >>>> It doesn't tell you much, the interesting stuff happens in the automounter.
> >>>>
> >>>> Is there a error log file for the automounter that is enabled by default?
> >>>> Is there an easy recipe for restarting the automounter with debugging output on?
> >>>
> >>> You need to ensure that debug logging is being recorded in syslog.
> >>> Ensure you are sending daemon.* somewhere.
> >>>
> >>> Then
> >>>
> >>> automount -l debug /net
> >>>
> >>> will start the debug logging and
> >>>
> >>> automount -l err /net
> >>>
> >>> will set it back to no logging.
> >>>
> >>> That is depending on the version of autofs you are using.
> >>>
> >>> If you don't see this option in the automount(8) man page you don't have
> >>> this option and all you can do is enable debug logging in the
> >>> configuration.
> >>>
> >>> Ian
> >>>
> >>>
> >>
> >
> >
>