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-144/2018-08-31-0649/flakey.log

The failure seems to be in the "samba-nt4" suite, whose build logs are available here:

   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-08-31-0649/samba-nt4.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-08-31-0649/samba-nt4.stdout
  
The top commit at the time of the failure was:

commit 83f0ac5c6da48c1a68f6a7b29992398735abb421
Author: Christof Schmitt <cs at samba.org>
Date:   Wed Aug 29 12:07:42 2018 -0700

    torture: Add test for directory_create_or_exist
    
    Signed-off-by: Christof Schmitt <cs at samba.org>
    Reviewed-by: Andreas Schneider <asn at samba.org>
    
    Autobuild-User(master): Christof Schmitt <cs at samba.org>
    Autobuild-Date(master): Thu Aug 30 21:19:31 CEST 2018 on sn-devel-144

and the last 50 lines of the stdout log were:

[524(2436)/570 at 20m38s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_dc:local)
[525(2437)/570 at 20m38s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_dc:local)
[526(2438)/570 at 20m38s] samba.wbinfo_simple.change-secret.domain=$DOMAIN(nt4_dc:local)
[527(2439)/570 at 20m38s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_dc:local)
[528(2440)/570 at 20m38s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_dc:local)
[529(2441)/570 at 20m38s] samba.wbinfo_simple.domain-users(nt4_dc:local)
[530(2442)/570 at 20m38s] samba.wbinfo_simple.domain-groups(nt4_dc:local)
[531(2443)/570 at 20m38s] samba.wbinfo_simple.name-to-sid=$DC_USERNAME(nt4_dc:local)
[532(2444)/570 at 20m38s] samba.wbinfo_simple.name-to-sid=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[533(2445)/570 at 20m38s] samba.wbinfo_simple.user-info=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[534(2446)/570 at 20m38s] samba.wbinfo_simple.user-groups=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[535(2447)/570 at 20m38s] samba.wbinfo_simple.authenticate=$DOMAIN/$DC_USERNAME%$DC_PASSWORD(nt4_dc:local)
[536(2448)/570 at 20m38s] samba.wbinfo_simple.allocate-uid(nt4_dc:local)
[537(2449)/570 at 20m39s] samba.wbinfo_simple.allocate-gid(nt4_dc:local)
[538(2450)/570 at 20m39s] samba.wbinfo_sids2xids.(nt4_dc:local)(nt4_dc:local)
[539(2451)/570 at 20m45s] samba.ntlm_auth.diagnostics(nt4_dc:local)(nt4_dc:local)
[540(2452)/570 at 20m45s] samba.ntlm_auth.(nt4_dc:local)(nt4_dc:local)
[541(2471)/570 at 20m46s] samba.wbinfo_simple.ping(nt4_member:local)
[542(2472)/570 at 20m46s] samba.wbinfo_simple.separator(nt4_member:local)
[543(2473)/570 at 20m46s] samba.wbinfo_simple.own-domain(nt4_member:local)
[544(2474)/570 at 20m46s] samba.wbinfo_simple.all-domains(nt4_member:local)
[545(2475)/570 at 20m47s] samba.wbinfo_simple.trusted-domains(nt4_member:local)
[546(2476)/570 at 20m47s] samba.wbinfo_simple.domain-info=BUILTIN(nt4_member:local)
[547(2477)/570 at 20m47s] samba.wbinfo_simple.domain-info=$DOMAIN(nt4_member:local)
[548(2478)/570 at 20m47s] samba.wbinfo_simple.online-status(nt4_member:local)
[549(2479)/570 at 20m47s] samba.wbinfo_simple.online-status.domain=BUILTIN(nt4_member:local)
[550(2480)/570 at 20m47s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_member:local)
[551(2481)/570 at 20m47s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_member:local)
UNEXPECTED(failure): samba.wbinfo_simple.check-secret.domain=SAMBA-TEST.wbinfo(nt4_member:local)
REASON: Exception: Exception: wbcCheckTrustCredentials(SAMBA-TEST): error code was NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND (0xc0000233)
failed to call wbcCheckTrustCredentials: WBC_ERR_AUTH_ERROR
Could not check secret
checking the trust secret for domain SAMBA-TEST via RPC calls failed

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
samba3.raw.notify(nt4_dc) -> 99
samba3.smb2.notify(nt4_dc) -> 79
samba3.rpc.samr.passwords.lockout(nt4_dc) -> 62
samba4.rpc.echo on ncacn_np with object(nt4_dc) -> 61
samba3.smb2.compound_find(nt4_dc) -> 57
samba3.smb2.compound_find(nt4_dc) -> 54
samba3.rpc.samr.passwords.pwdlastset(nt4_dc) -> 49
samba3.smb2.lease(nt4_dc) -> 45
samba3.raw.oplock(nt4_dc) -> 42
samba3.smb2.oplock(nt4_dc) -> 41
ERROR: test failed with exit code 1