[Samba] Duplicate PID

[Volker Lendecke]

On Mon, Feb 24, 2014 at 07:04:13PM +0200, Einat Ben Ezra wrote:
> Hi,
> 
> I'm using samba version 3.0.37 and i encountered a very strange and
> annoying phenomena
> when 2 different users from 2 different machines are getting the same PID
> from samba.
> (2 windows users that are trying to view documents on the CIFS share).
> 
> I did some google research on this problem and i found the following
> regarding such a problem:
> 
> "
> One can find references to problems like this, possibly affecting
> performance, back in 2001
> http://lists.samba.org/archive/samba-technical/2001-September/015658.html.
> I experience that also on an RHEL6 samba server. Is %CPU for pid 17666
> exceptionally high? If you look at the full smbstatus - do you see other
> users with the same PID as user toor? List open files for the process with
> lsof -p 17666 and verify if toor opens other user's files.
> 
> There are at least two theories what is causing this: 1. samba sometimes
> does not update it's state when clients are disconnected
> http://samba.2283325.n4.nabble.com/Closing-sessions-and-smbstatus-td2447307.html2.
> file locking (when one user accesses files of another user)
> https://bugzilla.samba.org/show_bug.cgi?id=8722
> "
> 
> *My questions are:*
> 
> 1.Can someone please throw a light on the problem? explain why this can
> happen?
> 2. How can i avoid such a problem of duplicate PID?

Two PIDs in the same box is not possible. It could be that
one smbd crashes hard and another smbd takes over the same
PID. But simultaneously -- no, impossible. It is perfectly
legal for one client machine to open a share twice. Later
versions have added the "reset on zero vc" option to deal
better with dead clients, and later versions also have added
provisions to deal properly with recycled PIDs. But we need
more information to see what is really your problem.

With best regards,

Volker Lendecke

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