Samba causing NT client app dropouts?

[Jeffery G. Smith]

We have a reasonably complicated network setup and have been suffering an
ongoing problem for over a year.  I have been working with Microsoft tech
support on the problem and so far we have been unable to find the cause.  I
recently gathered some information to indicate that samba is involved.  Any
help is greatly appreciated.

NT:  About 20 Windows NT 4.0SP3 Pentium workstations with one PDC and one
BDC.  The PDC offers file, printer and application service.

UNIX: About 20 SunOS/Solaris workstations with two Sparc5 servers.  One runs
SunOS and the other Solaris.  Both are running Samba 1.9.16p10

The Problem: When users log in, a login script mounts four drives, two from
the NT file server and one from each of the Sun servers.  Users frequently
run applications which reside on the NT shared drives, anything from PFE to
Netscape and MSOffice.  Periodically, these applications will just exit
unexpectedly.  This problem has been persisting for over a year.  Through an
enormous amount of debugging and testing it looks as though something is
causing the redirector to dismount and remount the NT shares causing the
applications to think the connection was lost.  Part of the catch was that
there seemed to be nothing I could do to force an occurrence of these
"dropouts".  Recently however I was able to find such a situation.  I have
removed the Samba mounts from the login scripts and now allow them to be
mounted as a result of the user profile.  This causes all the applications
in the startup group which reside on the NT app server to die immediately.

I use to experience these dropouts at least once a day.  Since I have
stopped using Samba to mount the drives on my workstation, I no longer have
this problem although it persists for other users.  I have been up and
running now for quite some time, but if I open a command prompt and so much
as net view the samba server, the applications I am running on the NT server
will fail.

I really hope not to get a lot of responses for simple things involving NT
or hardware.  This is not tied to any one Ethernet card or video card or
brand of computer, for instance.  I spent a week taking network usage data
to rule out a network load problem.  We are running 10Mb Ethernet over coax
and the problem is as likely to happen at 10% utilization as at 80%.
Microsoft has looked at several miles of network trace sessions between the
NT client and the NT server and there doesn't appear to be anything wrong
there either.  They would like to see similar network traces between the NT
client and the samba server and I plan to set that up soon.

I did want to post this here though to see if anyone else has experienced
this problem.  I posted this question a year ago without any response.  My
hope is that with the increased usage of samba over the recent past, someone
has encountered and fixed this little annoyance.  It might just be something
simple and configurable with samba that I have overlooked and suggestions of
that nature would be welcome.  Until now I hadn't looked at samba as the
cause of the problem, so not much research has been done on that front.

Again, your help is greatly appreciated as I would much prefer to continue
using Samba over an NFS solution.

--
Recuerde--nunca vuelva a utilizar el mismo perservativo

/* Jeffery G. Smith, MCSE, smithj at pobox.com       *
 *   BS-RHIT, MS-OSU, DJ-WMHD (aka Doc. Insomnia) *
 *   Physics Computer Support Team                *
 *   http://pobox.com/~smithj/                    */