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-144/2018-09-15-0140/flakey.log

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

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-09-15-0140/samba.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-09-15-0140/samba.stdout
  
The top commit at the time of the failure was:

commit f8df3f3499fd7421260fbe532bd6947d3c0ea8bd
Author: Volker Lendecke <vl at samba.org>
Date:   Fri Aug 3 12:45:59 2018 +0200

    mdssvc: Move a variable declaration closer to its use
    
    Signed-off-by: Volker Lendecke <vl at samba.org>
    Reviewed-by: Ralph Boehme <slow at samba.org>
    
    Autobuild-User(master): Volker Lendecke <vl at samba.org>
    Autobuild-Date(master): Fri Sep 14 10:48:47 CEST 2018 on sn-devel-144

and the last 50 lines of the stdout log were:

[749(3942)/848 at 52m18s] samba.tests.emulate.traffic_packet(ad_dc_ntvfs)
[750(4031)/848 at 53m28s] samba.tests.blackbox.traffic_replay(ad_dc_ntvfs)
[751(4037)/848 at 53m38s] samba.tests.blackbox.traffic_learner(ad_dc_ntvfs)
[752(4039)/848 at 53m39s] samba.tests.blackbox.traffic_summary(ad_dc_ntvfs)
[753(4039)/848 at 53m39s] samba.tests.blackbox.smbcontrol(ad_dc_ntvfs:local)
[754(4041)/848 at 53m41s] samba.tests.blackbox.smbcontrol(promoted_dc:local)
[755(4043)/848 at 53m42s] samba4.ldap.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[756(4082)/848 at 53m54s] samba4.tokengroups.krb5.python(ad_dc_ntvfs)(ad_dc_ntvfs:local)
[757(4092)/848 at 54m3s] samba4.tokengroups.ntlm.python(ad_dc_ntvfs)(ad_dc_ntvfs:local)
[758(4101)/848 at 54m11s] samba4.sam.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[759(4118)/848 at 54m15s] samba4.user_account_control.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[760(4129)/848 at 54m28s] samba4.schemaInfo.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[761(4131)/848 at 54m31s] samba.tests.dsdb_schema_attributes(ad_dc_ntvfs:local)
[762(4137)/848 at 54m44s] samba4.urgent_replication.python(ad_dc_ntvfs)(ad_dc_ntvfs:local)
[763(4145)/848 at 54m47s] samba4.ldap.dirsync.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[764(4169)/848 at 56m18s] samba4.ldap.match_rules.python(ad_dc_ntvfs)
[765(4203)/848 at 56m35s] samba4.ldap.notification.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[766(4206)/848 at 56m46s] samba4.ldap.sites.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[767(4217)/848 at 56m52s] samba4.ldap.sort.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[768(4224)/848 at 56m58s] samba4.ldap.vlv.python(ad_dc_ntvfs)(ad_dc_ntvfs)
[769(4239)/848 at 1h53s] samba4.ldap.linked_attributes.python(ad_dc_ntvfs)(ad_dc_ntvfs:local)
[770(4259)/848 at 1h58s] samba4.ldap.rodc.python(rodc)(rodc)
[771(4265)/848 at 1h1m1s] samba4.ldap.rodc_rwdc.python(rodc)(rodc:local)
[772(4285)/848 at 1h8m33s] samba4.drs.replica_sync_rodc.python(rodc)(rodc:local)
[773(4287)/848 at 1h8m41s] samba4.ldap.password_settings.python(ad_dc_ntvfs)
[774(4299)/848 at 1h9m19s] samba4.ldap_schema.python(ad_dc_ntvfs)(ad_dc_ntvfs)
UNEXPECTED(error): samba4.ldap_schema.python(ad_dc_ntvfs).__main__.SchemaTests.test_schemaUpdateNow(ad_dc_ntvfs)
REASON: Exception: Exception: Traceback (most recent call last):
  File "/memdisk/autobuild/fl/b1142103/samba/source4/dsdb/tests/python/ldap_schema.py", line 190, in test_schemaUpdateNow
    self.ldb.add_ldif(ldif)
  File "bin/python/samba/__init__.py", line 230, in add_ldif
    self.add(msg, controls)
LdbError: (21, "LDAP error 21 LDAP_INVALID_ATTRIBUTE_SYNTAX -  <0000200B: objectclass_attrs: attribute 'systemMustContain' on entry 'CN=test-Class1536964347,CN=Schema,CN=Configuration,DC=samba,DC=example,DC=com' contains at least one invalid value!> <>")

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) -> 451
samba4.ldap.vlv.python(ad_dc_ntvfs)(ad_dc_ntvfs) -> 235
samba4.rpc.samr.passwords.lockout on ncacn_np with (ad_dc_ntvfs) -> 226
samba4.rpc.samr.passwords.pwdlastset on ncacn_np with (ad_dc_ntvfs) -> 199
samba3.smbtorture_s3.vfs_aio_fork(simpleserver).RW2(simpleserver) -> 142
samba4.ldb.ldaps with options -U"$USERNAME%$PASSWORD"(ad_dc_ntvfs)(ad_dc_ntvfs) -> 118
samba4.raw.notify(ad_dc_ntvfs) -> 107
samba4.ldap.dirsync.python(ad_dc_ntvfs)(ad_dc_ntvfs) -> 91
samba.tests.emulate.traffic_packet(ad_dc_ntvfs) -> 70
samba.tests.samba_tool.user(ad_dc_ntvfs:local) -> 67
ERROR: test failed with exit code 1