Recent Samba (4.18.0+) winbind configuration ?

[Andreas Schneider]

On Tuesday, 11 April 2023 15:49:15 CEST Rowland Penny via samba-technical 
wrote:
> On 11/04/2023 13:32, Jiří Šašek - Solaris Prague via samba-technical wrote:
> > Story begins when Samba 4.14.0 changed its VFS so we decided to skip
> > 4.14.x and also 4.15.x releases to bundle it on Solaris but various
> > problems were also with later releases and we were only fixing issues in
> > 4.13.0 . Currently (4.18.0) the situation can called be critical so I
> > focused on recent release.
> > 
> > winbindd is giving up and I think the key could be in log message:
> > 
> > [2023/04/11 11:28:53.090661,  5, pid=1525, effective(0, 0), real(0, 0),
> > class=winbind] ../../source3/winbindd/wb_lookupname.c:
> > 52(wb_lookupname_send)
> > 
> >    WB command lookupname start.
> >    Search namespace 'smbsetup' and domain 'smbsetup' for name ''.
> > 
> > ...where "smbsetup" is my domain  ...and I have added core-dump here to
> > freeze the stack:
> > 
> > [2023/04/11 11:28:53.090780,  0, pid=1525, effective(0, 0), real(0, 0)]
> > ../../source3/lib/dumpcore.c:315(dump_core)
> > 
> >    dumping core in /var/samba/log/cores/winbindd
> > 
> > I went over such many frames of "tevent's" but I do not know where to
> > start evaluation. I only catch the (PIDL) generated code was
> > optimized-out by gcc (11.3.0) so I built the code with -O0 and now the
> > code is available.
> > 
> > In the mood of total madness I also tried ChatGPT which suspects my
> > smb.conf but answer on my question:
> > 
> > 
> > Q:
> > what was changed in idmap configuration in smb.conf between 4.13 and 4.18
> > ?
> > 
> > A:
> > There have been some changes to the idmap configuration in Samba between
> > version 4.13 and 4.18, although they may not necessarily be related to
> > the issue you're experiencing.
> > 
> > One notable change is that in Samba 4.18, the idmap config parameter has
> > been deprecated in favor of the idmap_ldb parameter. This new parameter
> > uses an LDB backend for id mapping, which allows for better performance
> > and scalability than the previous tdb backend.
> > 
> > Another change is that the idmap config parameter in Samba 4.18 now
> > accepts a backend option, which allows you to specify the backend to use
> > for id mapping. The options are rid, ad, autorid, and autorid_compat.
> > 
> > The rid backend continues to be the default, which means that if you
> > don't specify a backend explicitly, Samba will use the RID algorithm to
> > generate UIDs and GIDs.
> > 
> > In summary, if you're upgrading from Samba 4.13 to 4.18, you may need to
> > update your smb.conf to use the new idmap_ldb parameter and specify a
> > backend if you're not using the default rid backend.
> > 
> > ....looks suspectably because I can not find "idmap_ldb" in man smb.conf
> > so I asked again:
> > 
> > Q:
> > backend option of idmap config was available even in samba 4.0.0 smb.con
> > so what exactly has been changed in 4.18.0 ?
> > A:
> > Something went wrong. If this issue persists please contact us through
> > our help center at help.openai.com.
> > 
> > ...I do not want to push here the way how to shot-down the f'g ChatGPT
> > but I would like to know if something was really changed. I went through
> > the RELEASE NOTES and there is nothing directly concerns to idmap config
> > AFAIK
> > 
> > constraints:
> >   - net ads join works as usual include adding of "A" record to DNS
> > 
> >   - despite of successful join it looks DC can not be located:
> > [2023/04/11 11:28:53.083220,  1, pid=1525, effective(0, 0), real(0, 0),
> > class=rpc_parse] ../../librpc/ndr/ndr.c:490(ndr_print_
> > function_debug)
> > 
> >         wbint_PingDc: struct wbint_PingDc
> >            in: struct wbint_PingDc
> > 
> > [2023/04/11 11:28:53.083291,  1, pid=1525, effective(0, 0), real(0, 0),
> > class=rpc_parse] ../../librpc/ndr/ndr.c:490(ndr_print_
> > function_debug)
> > 
> >         wbint_InitConnection: struct wbint_InitConnection
> >            in: struct wbint_InitConnection
> >                dcname                   : *
> >                    dcname                   : ''
> > 
> > ...so it really looks like a stupid mis-configuration issue of mine.
> > 
> > Google is silent on all my attempts to ask "him".
> > 
> > If someone have some good idea please share it with me.
> > 
> > Many thanks,
> > Yura
> 
> Yes, stop asking chatGTP, you have made my day by supplying me with
> proof that chatGPT is STUPID!!!

It isn't really stupid, it just learns patterns it finds in a data set and 
then give you the results what it learned. This means that the data set is at 
fault here and the data set is "the Internet" :-)
 


-- 
Andreas Schneider                      asn at samba.org
Samba Team                             www.samba.org
GPG-ID:     8DFF53E18F2ABC8D8F3C92237EE0FC4DCC014E3D