samba - May 2004 - conflict between Realtek 8139 (client) and 3c2000T (server) NIC's with Samba?

Hi,

Last friday I changed the NIC in two of our Samba servers from a 3com 905b
(100mb) to a 3com 2000T (1000mb) to take advantage of our new switch which
supports gigabit.

One of the workstations (XP SP1, with all subsequent patches and hotfixes
and with an onboard Realtek 8139) then started
to have problems with the two Samba servers with the new NIC's. It could see
the network neighbourhood alright,
it could browse but when opening a file a time-out or error occurred.

In the logs lines like this:
syslog.1:May 15 17:00:56 kylie smbd[27625]: [2004/05/15 17:00:56, 0]
smbd/oplock.c:oplock_break(869)
syslog.1:May 15 17:00:56 kylie smbd[27625]:   oplock_break: client failure
in oplock break in file file.xls

I tried setting:
oplocks no
level2 oplocks no
in the smb.conf
but no luck.
(mind you: all other workstations worked just fine, it was just this one el
cheapo barebone). There was also no problem in reaching another Samba server
with an 100 MB 3c905 NIC.

I then tried updating to Samba 3.0.4 but still no luck. Had fun though with
updating the recycle bin etc ...

I then tried using a different PC also with a Realtek 8139 card: same
problem! So I put another NIC in the offending machine and presto:
everything worked just fine.

Can someone explain this and possibly suggest another solution? We have a
number of PC's with Realtek's (I know: they are not hgh quality cards to
put
it mildly) and would
rather not replace them all. I can't think what the cause of the problem is:
a NIC that otherwise works fine (surfing, even from the same machine which
had the Samba server or any other network activitity) causes problems with
Samba. I could understand it if the Samba server had the Realtek NIC, but I
never have had any problems with 3com cards.

Googling turned up no relevant informatie, so does anybody on this list have
an idea? If additional info is needed I can provide it.

Thanks,
Bart van Dijck

On Tue, May 25, 2004 at 06:01:25PM +0200, Bart van Dijck
wrote:
> 
> Can someone explain this and possibly suggest another solution? We have a
> number of PC's with Realtek's (I know: they are not hgh quality
cards to put
> it mildly) and would
> rather not replace them all. I can't think what the cause of the
problem is:
> a NIC that otherwise works fine (surfing, even from the same machine which
> had the Samba server or any other network activitity) causes problems with
> Samba. I could understand it if the Samba server had the Realtek NIC, but I
> never have had any problems with 3com cards.
We (Samba) live so far above the network card drivers it's not funny.
We're just an application - admittedly one that stresses the network
quite a bit due to the speed.

I'm afraid you may have found some intrinsic problems with either the
cards or the driver for the card. The only way to change this with
Samba is to add a 'go slower' switch into smbd, which as I'm sure
you'll understand we're loathe to do :-).

Jeremy.