autobuild[sn-devel-144]: intermittent test failure detected

[autobuild]

The autobuild test system (on sn-devel-144) has detected an intermittent failing test in 
the current master tree.

The autobuild log of the failure is available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2019-01-31-1850/flakey.log

The failure seems to be in the "samba-py2" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2019-01-31-1850/samba-py2.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2019-01-31-1850/samba-py2.stdout
  
The top commit at the time of the failure was:

commit 4ecdcc4b462d03bec3ec36ba1b90f45d9977be8b
Author: Gary Lockyer <gary at catalyst.net.nz>
Date:   Tue Jan 29 11:34:31 2019 +1300

    man pages: document prefork process model
    
    Document the process model options -M
    
    BUG: https://bugzilla.samba.org/show_bug.cgi?id=13765
    
    Signed-off-by: Gary Lockyer <gary at catalyst.net.nz>
    Signed-off-by: Tim Beale <timbeale at catalyst.net.nz>
    Reviewed-by: Douglas Bagnall <douglas.bagnall at catalyst.net.nz>
    
    Autobuild-User(master): Tim Beale <timbeale at samba.org>
    Autobuild-Date(master): Thu Jan 31 04:25:14 CET 2019 on sn-devel-144

and the last 50 lines of the stdout log were:

[33(263)/85 at 7m54s] samba.tests.emulate.traffic_packet.python2(ad_dc_ntvfs)
[34(352)/85 at 9m49s] samba.tests.blackbox.traffic_replay.python2(ad_dc_ntvfs)
[35(357)/85 at 10m16s] samba.tests.blackbox.traffic_learner.python2(ad_dc_ntvfs)
[36(359)/85 at 10m16s] samba.tests.blackbox.traffic_summary.python2(ad_dc_ntvfs)
[37(359)/85 at 10m17s] samba.tests.blackbox.smbcontrol.python2(ad_dc_ntvfs:local)
[38(361)/85 at 10m18s] samba.tests.blackbox.smbcontrol.python2(promoted_dc:local)
[39(363)/85 at 10m19s] samba4.schemaInfo.python(ad_dc_ntvfs).python2(ad_dc_ntvfs)
[40(365)/85 at 10m23s] samba.tests.dsdb_schema_attributes.python2(ad_dc_ntvfs:local)
[41(371)/85 at 10m43s] samba4.ldap.sort.python.python2(ad_dc_ntvfs)
[42(378)/85 at 10m51s] samba4.drs.replica_sync_rodc.python(rodc).python2(rodc:local)
[43(380)/85 at 11m4s] samba4.ldap.passwordsettings.python.python2(ad_dc_ntvfs)
[44(392)/85 at 11m51s] samba4.tombstone_reanimation.python.python2(ad_dc_ntvfs)
[45(404)/85 at 11m58s] samba.tests.upgradeprovisionneeddc.python2(ad_dc_ntvfs:local)
[46(415)/85 at 12m1s] samba.tests.samba_tool.rodc.python2(rodc:local)
[47(424)/85 at 12m35s] samba4.drs.ridalloc_exop.python(vampire_dc).python2(vampire_dc)
[48(435)/85 at 15m30s] samba4.drs.samba_tool_drs.python(vampire_dc).python2(vampire_dc:local)
[49(449)/85 at 17m28s] samba4.drs.samba_tool_drs_showrepl.python(vampire_dc).python2(vampire_dc:local)
[50(453)/85 at 17m42s] samba4.drs.replica_sync.python(vampire_dc).python2(vampire_dc:local)
[51(469)/85 at 19m30s] samba4.drs.delete_object.python(vampire_dc).python2(vampire_dc)
[52(471)/85 at 19m41s] samba4.drs.fsmo.python(vampire_dc).python2(vampire_dc)
[53(476)/85 at 19m53s] samba4.drs.repl_move.python(vampire_dc).python2(vampire_dc)
[54(497)/85 at 21m50s] samba4.drs.getnc_exop.python(vampire_dc).python2(vampire_dc)
[55(509)/85 at 22m3s] samba4.drs.getnc_unpriv.python(vampire_dc).python2(vampire_dc)
[56(513)/85 at 22m8s] samba4.drs.link_conflicts.python(vampire_dc).python2(vampire_dc)
[57(525)/85 at 24m44s] samba4.drs.samba_tool_drs.python(promoted_dc).python2(promoted_dc:local)
UNEXPECTED(error): samba4.drs.samba_tool_drs.python(promoted_dc).python2.samba_tool_drs.SambaToolDrsTests.test_samba_tool_kcc(promoted_dc:local)
REASON: Exception: Exception: Traceback (most recent call last):
  File "/memdisk/autobuild/fl/b869711/samba-py2/source4/torture/drs/python/samba_tool_drs.py", line 81, in test_samba_tool_kcc
    self.cmdline_creds))
  File "bin/python/samba/tests/__init__.py", line 447, in check_output
    raise BlackboxProcessError(retcode, line, stdoutdata, stderrdata)
BlackboxProcessError: Command 'python3 /memdisk/autobuild/fl/b869711/samba-py2/bin/samba-tool drs kcc localdc -USAMBADOMAIN/Administrator%locDCpass1'; shell True; exit status 255; stdout: ''; stderr: 'ERROR(runtime): DsExecuteKCC failed - (3221356597, 'The operation cannot be performed.')
'

FAILED (0 failures, 1 errors and 0 unexpected successes in 0 testsuites)

A summary with detailed information can be found in:
  ./bin/ab/summary
TOP 10 slowest tests
samba4.drs.ridalloc_exop.python(vampire_dc).python2(vampire_dc) -> 175
samba4.drs.link_conflicts.python(vampire_dc).python2(vampire_dc) -> 155
samba4.drs.samba_tool_drs.python(vampire_dc).python2(vampire_dc:local) -> 118
samba4.drs.repl_move.python(vampire_dc).python2(vampire_dc) -> 117
samba.tests.emulate.traffic_packet.python2(ad_dc_ntvfs) -> 115
samba4.drs.replica_sync.python(vampire_dc).python2(vampire_dc:local) -> 109
samba.tests.samba_tool.user.python2(ad_dc_ntvfs:local) -> 70
samba4.ldap.passwordsettings.python.python2(ad_dc_ntvfs) -> 46
samba.tests.samba_tool.user_wdigest.python2(ad_dc_ntvfs:local) -> 40
samba.tests.samba_tool.rodc.python2(rodc:local) -> 34
ERROR: test failed with exit code 1