samba - Dec 2015 - The case of the disconnecting network shares

Hi Jeremy,

No, I don't mean "deadtime". I mean auto disconnect. Specifically,
the
command "net config server /autodisconnect:-1" was run on each client 
machine. If deadtime is a server configuration item perhaps you could 
point me in the direction of some documentation where that is covered. 
The documentation for smb.conf is, to put it very mildly, incomplete.

Wireshark would be impractical in this case because I can't predict when 
the disconnects will occur, or even if they will occur for any given 
client, and this is a very busy file server, even during the night. 
Therefore, the logs would be far too immense to be useful without first 
knowing exactly what event(s) I'm looking for.

regards,
John


On 15/12/15 15:55, Jeremy Allison wrote:
> On Tue, Dec 15, 2015 at 02:48:21PM +1100, John Gardeniers wrote:
>> We recently completed our Samba 3 to Samba 4 transition without too
>> many serious problems but one rather annoying issue has cropped up
>> since the migration. Network shares on our file server become
>> disconnected overnight, whether idle or not. This was never a
>> problem with Samba 3 but since upgrading Samba on the server to
>> version 4 and joining it to the Samba 4 AD domain this problem is
>> happening most, but not all, nights. This is merely a minor nuisance
>> for most of our staff but is a serious problem for those who need to
>> run overnight jobs over those shares. The inconsistency makes it
>> even more puzzling.
>>
>> We have set the auto disconnect time to -1 to disable it on all
>> clients but that has made absolutely no difference. Samba itself
>> shows nothing in the logs that suggests there was any sort of
>> problem during the night and I have not been able to ascertain
>> whether all clients get disconnected at the same time or whether it
>> occurs at various times.
>>
>> Can anyone shed any light on this and suggest possible reasons
>> and/or solutions?
> If you mean "deadtime" the default is zero, and that
> means don't disconnect.
>
> Try getting a wireshark trace around the disconnect,
> if that's possible. That should tell you if it's the
> client or server initiating the disconnect.
>
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On Tue, Dec 15, 2015 at 04:07:55PM +1100, John Gardeniers
wrote:
> Hi Jeremy,
> 
> No, I don't mean "deadtime". I mean auto disconnect.
Specifically,
> the command "net config server /autodisconnect:-1" was run on
each
> client machine.
Ah - didn't know auto disconnect was a client feature,
but then again I don't use Windows :-).
> If deadtime is a server configuration item perhaps
> you could point me in the direction of some documentation where that
> is covered. The documentation for smb.conf is, to put it very
> mildly, incomplete.
That's not true. smb.conf documentation is certainly
complete, as we generate the config parameters that
go into the Samba code from the xml docs for each
parameter.

man smb.conf

Search for deadtime.

On Tue, Dec 15, 2015 at 04:07:55PM +1100, John Gardeniers
wrote:
> Wireshark would be impractical in this case because I can't predict
> when the disconnects will occur, or even if they will occur for any
> given client, and this is a very busy file server, even during the
> night. Therefore, the logs would be far too immense to be useful
> without first knowing exactly what event(s) I'm looking for.
You can limit tcpdump to a single client with "host
<ip-address>". And
multi-gigabyte traces can be split up. I'm used to that :-)

Volker

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http://www.sernet.de, mailto:kontakt at sernet.de

Hi Jeremy,

Using Samba without Windows seems rather pointless, as no other OS needs 
it, nor can test it to any truly useful extent.

Thanks for point out the man page, which I've always taken as be 
referring to Samba 3, not Samba 4. I can only wonder why there's a site 
dedicated to Samba 4 documentation and this information isn't there.

If the default deadtime = 0 and we haven't changed it then that's 
obviously not the culprit and I need to keep looking for a cause.

regards,
John


On 15/12/15 16:35, Jeremy Allison wrote:
> On Tue, Dec 15, 2015 at 04:07:55PM +1100, John Gardeniers wrote:
>> Hi Jeremy,
>>
>> No, I don't mean "deadtime". I mean auto disconnect.
Specifically,
>> the command "net config server /autodisconnect:-1" was run on
each
>> client machine.
> Ah - didn't know auto disconnect was a client feature,
> but then again I don't use Windows :-).
>
>> If deadtime is a server configuration item perhaps
>> you could point me in the direction of some documentation where that
>> is covered. The documentation for smb.conf is, to put it very
>> mildly, incomplete.
> That's not true. smb.conf documentation is certainly
> complete, as we generate the config parameters that
> go into the Samba code from the xml docs for each
> parameter.
>
> man smb.conf
>
> Search for deadtime.
>