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-144/2019-03-28-1847/flakey.log

The failure seems to be in the "samba-ad-dc-2" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2019-03-28-1847/samba-ad-dc-2.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2019-03-28-1847/samba-ad-dc-2.stdout
  
The top commit at the time of the failure was:

commit c68d9c9ef367c1e85619ac2d027a0a425164ca8a
Author: David Disseldorp <ddiss at samba.org>
Date:   Mon Mar 25 18:06:15 2019 +0100

    vfs_snapper: drop unneeded fstat handler
    
    fstat is handle based, and unlike vfs_shadow_copy2, we don't need to
    make any changes to the returned sbuf, so remove the existing handler
    which does nothing.
    
    Bug: https://bugzilla.samba.org/show_bug.cgi?id=13858
    
    Signed-off-by: David Disseldorp <ddiss at samba.org>
    Reviewed-by: Jeremy Allison <jra at samba.org>
    
    Autobuild-User(master): Jeremy Allison <jra at samba.org>
    Autobuild-Date(master): Wed Mar 27 18:21:38 UTC 2019 on sn-devel-144

and the last 50 lines of the stdout log were:

[20(133)/66 at 1m52s] samba.wbinfo_simple.name-to-sid=$DOMAIN/$DC_USERNAME(rodc:local)
[21(134)/66 at 1m53s] samba.wbinfo_simple.user-info=$DOMAIN/$DC_USERNAME(rodc:local)
[22(135)/66 at 1m53s] samba.wbinfo_simple.user-groups=$DOMAIN/$DC_USERNAME(rodc:local)
[23(136)/66 at 1m53s] samba.wbinfo_simple.authenticate=$DOMAIN/$DC_USERNAME%$DC_PASSWORD(rodc:local)
[24(137)/66 at 1m53s] samba.wbinfo_simple.allocate-uid(rodc:local)
[25(138)/66 at 1m54s] samba.wbinfo_simple.allocate-gid(rodc:local)
[26(139)/66 at 1m54s] samba.wbinfo_sids2xids.(rodc:local)(rodc:local)
[27(140)/66 at 2m9s] samba.tests.ntlm_auth(rodc:local)
[28(153)/66 at 2m15s] samba.tests.encrypted_secrets(vampire_dc:local)
[29(155)/66 at 2m16s] samba.tests.py_credentials(vampire_dc)
[30(163)/66 at 2m19s] samba4.ldap.rodc.python(rodc)(rodc)
[31(169)/66 at 2m22s] samba4.ldap.rodc_rwdc.python(rodc)(rodc:local)
[32(189)/66 at 9m56s] samba4.drs.replica_sync_rodc.python(rodc)(rodc:local)
[33(191)/66 at 10m3s] samba4.rpc.samr.large-dc.one(vampire_dc)
[34(194)/66 at 10m14s] samba4.rpc.samr.large-dc.two(vampire_dc)
[35(197)/66 at 10m26s] samba4.rpc.echo(rodc)
[36(207)/66 at 10m30s] samba4.rpc.echo(rodc:local)
[37(217)/66 at 10m35s] samba4.rpc.echo.testallowed(rodc:local)
[38(227)/66 at 10m38s] samba4.rpc.echo.testdenied(rodc:local)
[39(237)/66 at 10m41s] samba4.blackbox.smbclient(rodc:local)(rodc:local)
[40(239)/66 at 10m43s] samba.tests.samba_tool.rodc(rodc:local)
[41(248)/66 at 11m17s] samba.blackbox.rpcclient_samlogon(rodc:local)
[42(252)/66 at 11m18s] samba.blackbox.rpcclient_samlogon_testallowed(rodc:local)
[43(256)/66 at 11m19s] samba.blackbox.rpcclient_samlogon_testdenied(rodc:local)
[44(260)/66 at 11m20s] samba4.drs.ridalloc_exop.python(vampire_dc)(vampire_dc)
[45(271)/66 at 14m30s] samba4.drs.samba_tool_drs.python(vampire_dc)(vampire_dc:local)
UNEXPECTED(error): samba4.drs.samba_tool_drs.python(vampire_dc).samba_tool_drs.SambaToolDrsTests.test_samba_tool_kcc(vampire_dc:local)
REASON: Exception: Exception: Traceback (most recent call last):
  File "/memdisk/autobuild/fl/b1679513/samba-ad-dc-2/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)
samba.tests.BlackboxProcessError: Command 'python3 /memdisk/autobuild/fl/b1679513/samba-ad-dc-2/bin/samba-tool drs kcc localdc -USAMBADOMAIN/Administrator%locDCpass1'; shell True; exit status 255; stdout: 'b'''; stderr: 'b"ERROR(runtime): DsExecuteKCC failed - (3221356597, 'The operation cannot be performed.')\n"'

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.ldap.rodc_rwdc.python(rodc)(rodc:local) -> 454
samba4.drs.ridalloc_exop.python(vampire_dc)(vampire_dc) -> 190
samba.tests.samba_tool.rodc(rodc:local) -> 34
samba.wbinfo_sids2xids.(rodc:local)(rodc:local) -> 14
samba4.rpc.samr.large-dc.one(vampire_dc) -> 11
samba4.rpc.samr.large-dc.two(vampire_dc) -> 11
samba4.drs.replica_sync_rodc.python(rodc)(rodc:local) -> 7
samba.tests.ntlm_auth(rodc:local) -> 6
samba4.rpc.echo(rodc:local) -> 5
samba.tests.dns(vampire_dc:local) -> 5
ERROR: test failed with exit code 1