[Samba] weekly samba kerberos failure

[Jeremy Allison]

On Mon, Jun 21, 2010 at 12:39:09PM -0400, Hong K Phooey wrote:
> We have a service on our windows system that drops files onto a samba share every 10 minutes.  This has worked fine, except after one week, the system will fail.  We usually restart samba and winbind on the linux side, and then restart the service on the windows box to resolve the issue.
> 
> This week we decieded to let it fail, and after an hour it seemed to allow connections to the samba share.  Here is the log file of the failures:
> 
>   172.19.6.60 (172.19.6.60) closed connection to service lorian
> [2010/06/21 09:40:03,  1] smbd/sesssetup.c:342(reply_spnego_kerberos)
>   Failed to verify incoming ticket with error NT_STATUS_LOGON_FAILURE!
> 
> This repeats every minute until 10:33 am, when the service was able to reconnect to the share.
> 
> Is there a reason why this would fail every week at the same time?  Do these settings have anything to do with the issue?  
> 
> Default: idmap cache time = 604800 (one week)
> Default: machine password timeout = 604800
> 
> For the machine password timeout, is it necessary for it to update this often.  Can it be set to only attempt once per year, longer?

You can stop it updating the machine password by setting
"machine password timeout = 0".

This looks like an issue with the machine account
password being changed.

Jeremy