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-144/2018-11-28-1259/flakey.log

The failure seems to be in the "samba-purepy3-ad-dc-2" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-11-28-1259/samba-purepy3-ad-dc-2.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-11-28-1259/samba-purepy3-ad-dc-2.stdout
  
The top commit at the time of the failure was:

commit fde9f7c81b42419e71b2fc8c31d92db4a05176af
Author: Tim Beale <timbeale at catalyst.net.nz>
Date:   Tue Nov 13 13:22:41 2018 +1300

    CVE-2018-16857 dsdb/util: Add better default lockOutObservationWindow
    
    Clearly the lockOutObservationWindow value is important, and using a
    default value of zero doesn't work very well.
    
    This patch adds a better default value (the domain default setting of 30
    minutes).
    
    BUG: https://bugzilla.samba.org/show_bug.cgi?id=13683
    
    Signed-off-by: Tim Beale <timbeale at catalyst.net.nz>
    Reviewed-by: Andrew Bartlett <abartlet at samba.org>
    
    Autobuild-User(master): Karolin Seeger <kseeger at samba.org>
    Autobuild-Date(master): Wed Nov 28 11:31:14 CET 2018 on sn-devel-144

and the last 50 lines of the stdout log were:


* Comparing [CONFIGURATION] context...

* DN lists have different size: 1616 != 1615

* DNs found only in tdb:///memdisk/autobuild/fl/b1731505/samba-purepy3-ad-dc-2/bin/ab/backupfromdc/private/sam.ldb:
    CN=69B6F314-4C2F-4D67-8E28-CAC1987CD07B,CN=NTDS SETTINGS,CN=BACKUPFROMDC,CN=SERVERS,CN=BACKUP-SITE,CN=SITES,CN=CONFIGURATION,DC=BACKUPDOM,DC=SAMBA,DC=EXAMPLE,DC=COM

* Objects to be compared: 1615

* Result for [CONFIGURATION]: FAILURE

SUMMARY
---------

* Comparing [SCHEMA] context...

* Objects to be compared: 1550

* Result for [SCHEMA]: SUCCESS

* Comparing [DNSDOMAIN] context...

* Objects to be compared: 39

* Result for [DNSDOMAIN]: SUCCESS

* Comparing [DNSFOREST] context...

* Objects to be compared: 17

* Result for [DNSFOREST]: SUCCESS
ERROR: Compare failed: -1

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

A summary with detailed information can be found in:
  ./bin/ab/summary
TOP 10 slowest tests
samba.tests.samba_tool.dnscmd(chgdcpass:local) -> 239
samba.tests.domain_backup(restoredc:local) -> 157
samba.tests.dcerpc.raw_protocol(chgdcpass) -> 47
samba4.blackbox.kinit(fl2000dc:local)(fl2000dc:local) -> 19
samba4.net.api.become.dc(fl2000dc) -> 10
samba.wbinfo_sids2xids.(chgdcpass:local)(chgdcpass:local) -> 8
samba4.rpc.pac on ncacn_np(fl2000dc) -> 8
samba4.blackbox.chgdcpass(chgdcpass) -> 7
samba.tests.samba_tool.sites(chgdcpass:local) -> 5
samba4.blackbox.ldapcmp_restore(offlinebackupdc) -> 5
ERROR: test failed with exit code 1