Subject: Re: [vserver] autofs failing to umount in guest
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Tue, 29 Dec 2009 16:23:10 +0100

On Tue, Dec 29, 2009 at 09:36:58PM +1100, Fog_Watch wrote:
> On Tue, 29 Dec 2009 09:06:37 +0100
> Herbert Poetzl <herbert@13thfloor.at> wrote:

> > try with chroot (from the host) into the guest
> > data (root dir), otherwise it is probably apples
> > and oranges ...
> Is this what you were thinking:

> hostname mnt # mount -t proc none /vservers/as/proc/
> hostname mnt # chroot /vservers/as/ /bin/bash
> hostname / # /etc/init.d/autofs start
> * Starting
> automounter...                                                 [ ok ]
> hostname / # df | grep cdrom
> df: `/usr/portage/packages': No such file or directory
> hostname / # cd /mnt/cdrom
> hostname cdrom # df | grep cdrom
> df: `/usr/portage/packages': No such file or directory
> /dev/sr0                717098    717098         0
> 100% /mnt/removables/cdrom
> hostname cdrom # cd ~
> hostname ~ # df | grep cdrom
> df: `/usr/portage/packages': No such file or directory
> hostname ~ # exit
> exit
> hostname mnt # umount /vservers/as/proc/

> That is, when chrooted into the vserver autofs operates correctly.

> > please try with lsof +d and lsof +D as well ...
> When in the vserver:

> hostname ~ # df | grep cdrom
> /dev/sr0                717098    717098         0
> 100% /mnt/removables/cdrom
> hostname ~ # lsof +d /mnt
> hostname ~ # lsof +D /mnt
> hostname ~ # 

> Nothin' much there.

good, then the next step is to try in a context but on
the host filesystem, i.e. start autofs with:
 
  chcontext --xid 42 -- /etc/init.d/autofs start

and check if that fails, if so, run strace -fF on
autofs with and without the chcontext, i.e.:

  strace -fF /etc/init.d/autofs start
  chcontext --xid 42 -- strace -fF /etc/init.d/autofs start

and upload the output of each of them somewhere

TIA,
Herbert

> Regards
> Fog_Watch
> -- 
> Lose wait.  Get Gentoo.