dead lock (autofs and/or mount)

dead lock (autofs and/or mount)

[cedric briner]

sarge
autofs-4.1.3
mount-2.12p
uname -r : 2.6.8-3-686

hello,
I'm having such difficulties between the mount and the autofs package.
When autofs want to mount a resource which is not available, i get into 
this situation:

in my situation a nested mount in unavailable!

# ps -efH

root      4588     1  0 Oct25 ?        00:00:00   /usr/sbin/automount
--pid-file=/var/run/autofs/_home_photom.pid --timeout=300 --ghost
/home/photom yp auto_home_photom

root     21442  4588  0 13:41 ?        00:00:00     /usr/sbin/automount
--pid-file=/var/run/autofs/_home_photom.pid --timeout=300 --ghost
/home/photom yp auto_home_photom

root     21444 21442  0 13:41 ?        00:00:00       [mount] <defunct>

root     21450     1  0 13:41 ?        00:00:00   mount --
obssb13:/export/diskA2/backup/carrier


# ypcat -k auto_home_photom | grep carrier
carrier -bg / obssb6:/export/diskA1/& /unsaved obssb6:/export/diskA2/&
  /backup obssb13:/export/diskA2/backup/&

do you have any idea how I can surpass such situation

thanks.

Ced

-- 

Cedric BRINER
Geneva - Switzerland

Re: dead lock (autofs and/or mount)

[Jeff Moyer]

==> Regarding [autofs] dead lock (autofs and/or mount); cedric briner <work@infomaniak.ch> adds:

work> # ypcat -k auto_home_photom | grep carrier
work> carrier -bg / obssb6:/export/diskA1/& /unsaved obssb6:/export/diskA2/&
work>   /backup obssb13:/export/diskA2/backup/&

Never ever use the "-bg" option in an automount map.  Ian, do we filter
that out in the new code?  If not, I'll make a note on my TODO list.

-Jeff

Re: dead lock (autofs and/or mount)

[Ian Kent]

On Fri, 2006-11-03 at 18:07 +0100, cedric briner wrote:
> sarge
> autofs-4.1.3
> mount-2.12p
> uname -r : 2.6.8-3-686
> 
> hello,
> I'm having such difficulties between the mount and the autofs package.
> When autofs want to mount a resource which is not available, i get into 
> this situation:
> 
> in my situation a nested mount in unavailable!
> 
> # ps -efH
> 
> root      4588     1  0 Oct25 ?        00:00:00   /usr/sbin/automount
> --pid-file=/var/run/autofs/_home_photom.pid --timeout=300 --ghost
> /home/photom yp auto_home_photom
> 
> root     21442  4588  0 13:41 ?        00:00:00     /usr/sbin/automount
> --pid-file=/var/run/autofs/_home_photom.pid --timeout=300 --ghost
> /home/photom yp auto_home_photom
> 
> root     21444 21442  0 13:41 ?        00:00:00       [mount] <defunct>
> 
> root     21450     1  0 13:41 ?        00:00:00   mount --
> obssb13:/export/diskA2/backup/carrier
> 
> # ypcat -k auto_home_photom | grep carrier
> carrier -bg / obssb6:/export/diskA1/& /unsaved obssb6:/export/diskA2/&
>   /backup obssb13:/export/diskA2/backup/&

Don't use -bg.

How can autofs mount all entries of a multi-mount, with potential
nesting, if a mount operation is put into background. When a mount
operation is put into the background mount returns success which may not
actually true.

This is a sure way to break multi-mounts such as you are using here.

Ian

Re: dead lock (autofs and/or mount)

[Ian Kent]

On Fri, 2006-11-03 at 13:56 -0500, Jeff Moyer wrote:
> ==> Regarding [autofs] dead lock (autofs and/or mount); cedric briner <work@infomaniak.ch> adds:
> 
> work> # ypcat -k auto_home_photom | grep carrier
> work> carrier -bg / obssb6:/export/diskA1/& /unsaved obssb6:/export/diskA2/&
> work>   /backup obssb13:/export/diskA2/backup/&
> 
> Never ever use the "-bg" option in an automount map.  Ian, do we filter
> that out in the new code?  If not, I'll make a note on my TODO list.

Yep. That was in the initial patch set merged into git for 4.1.5.

Ian

Re: dead lock (autofs and/or mount)

[cedric briner]

> Don't use -bg.
> 
I'm not anymore... and it rocks

For the story, we were using this bg option on Solaris, and it perfeclty 
works.

thank you for your _precious_ help !

Ced.

-- 

Cedric BRINER
Geneva - Switzerland

Re: dead lock (autofs and/or mount)

[Peter Staubach]

cedric briner wrote:
>> Don't use -bg.
>>
>>     
> I'm not anymore... and it rocks
>
> For the story, we were using this bg option on Solaris, and it perfeclty 
> works.
>
> thank you for your _precious_ help !

Yes, that is because the Solaris automountd ignores the "bg" and "fg"
options.  They weren't correct to use there either, but it was harmless.

       ps