[PATCHES] Add 'net tdb' command to allow debugging of contended records in locking.tdb

[Christof Schmitt]

On Fri, Apr 28, 2017 at 03:04:59PM -0700, Christof Schmitt via samba-technical wrote:
> On Wed, Apr 26, 2017 at 11:54:12AM -0700, Christof Schmitt via samba-technical wrote:
> > On Tue, Apr 25, 2017 at 01:09:14PM +0200, vl at samba.org wrote:
> > > Hi, Christof!
> > > 
> > > On Thu, Apr 13, 2017 at 01:00:19PM -0700, Christof Schmitt via samba-technical wrote:
> > > > One problem in cluster environments can be contended access to the same
> > > > file, in which case ctdb has to transfer the locking.tdb record across
> > > > nodes for every open and close of that file.
> > > 
> > > Attached find two patches that you might want to take into
> > > consideration. I haven't run a full autobuild on the patches, but if
> > > you find my two to-SQUASH patches acceptable, Reviewed-By: me.
> > 
> > Thank you. I added the two changes and will push the patches to
> > autobuild.
> 
> I tried to push these to autobuild, but get a consistent failure at:
> 
> [1689(10768)/2100 at 1h51m38s] samba4.blackbox.trust_ntlm(fl2008r2dc:local)
> [1690(10790)/2100 at 1h51m39s] samba4.blackbox.trust_ntlm(fl2003dc:local)
> [1691(10812)/2100 at 1h51m40s] samba4.blackbox.trust_ntlm(ad_member:local)
> UNEXPECTED(error): samba4.blackbox.trust_ntlm.Test01 rpcclient getusername with LOCALADMEMBERtime: 2017-04-28 01:12:50.225336Z(ad_member:local)
> REASON: Exception: Exception: Test was never started
> UNEXPECTED(error): samba4.blackbox.trust_ntlm.Test01 rpcclient getusername with LOCALADMEMBERtime: 2017-04-28 01:12:50.223650Z(ad_member:local) (samba.subunit.RemotedTestCase)
> REASON: was started but never finished!
> 
> FAILED (0 failures, 2 errors and 0 unexpected successes in 0 testsuites)
> 
> 
> I am still debugging, something seems to be tripping up the tracking in
> selftest/subunithelper.py. Running a 'make test' for the affected testcase and
> the new net_tdb testcase works.

FYI,

the same problem also hits when trying to push a different patchset (the
idmap_rfc2307 fixes). The exact same problem also hits on a private
autobuild build with just some debugging enabled. The output after
"rpcclient getusername with" is suspicious; it is supposed to be the
user name, but here it shows the test environment and then also adds the
timestamp. Adding the timestamp in the name is likely the cause for the
subunithelp.py not being able to identify the running test. I am still
trying to find out why this is messed up in the first place.

Christof