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

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?

regards,
John

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.

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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