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-144/2018-06-27-0635/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-144/2018-06-27-0635/samba-nt4.stderr
   https://git.samba.org/autobuild.flakey.sn-devel-144/2018-06-27-0635/samba-nt4.stdout
  
The top commit at the time of the failure was:

commit 562ec950fc27ae498c53a2188329530651e64e05
Author: Tim Beale <timbeale at catalyst.net.nz>
Date:   Fri Jun 15 11:54:37 2018 +1200

    remove_dc: Fix removal of an old Windows DC
    
    Windows has 'CN=DNS Settings' child object underneath the Server object.
    This was causing the removal of the server object in remove_dc() to
    fail.
    
    Noticed this problem while testing the backup/restore tool manually
    against a Windows VM.
    
    BUG: https://bugzilla.samba.org/show_bug.cgi?id=13484
    
    Signed-off-by: Tim Beale <timbeale at catalyst.net.nz>
    Reviewed-by: Andrew Bartlett <abartlet at samba.org>
    Reviewed-by: Gary Lockyer <gary at catalyst.net.nz>
    
    Autobuild-User(master): Gary Lockyer <gary at samba.org>
    Autobuild-Date(master): Tue Jun 26 23:32:51 CEST 2018 on sn-devel-144

and the last 50 lines of the stdout log were:

[455(2339)/502 at 18m11s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_dc:local)
[456(2340)/502 at 18m11s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_dc:local)
[457(2341)/502 at 18m11s] samba.wbinfo_simple.change-secret.domain=$DOMAIN(nt4_dc:local)
[458(2342)/502 at 18m11s] samba.wbinfo_simple.check-secret.domain=$DOMAIN(nt4_dc:local)
[459(2343)/502 at 18m11s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_dc:local)
[460(2344)/502 at 18m12s] samba.wbinfo_simple.domain-users(nt4_dc:local)
[461(2345)/502 at 18m12s] samba.wbinfo_simple.domain-groups(nt4_dc:local)
[462(2346)/502 at 18m12s] samba.wbinfo_simple.name-to-sid=$DC_USERNAME(nt4_dc:local)
[463(2347)/502 at 18m12s] samba.wbinfo_simple.name-to-sid=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[464(2348)/502 at 18m12s] samba.wbinfo_simple.user-info=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[465(2349)/502 at 18m12s] samba.wbinfo_simple.user-groups=$DOMAIN/$DC_USERNAME(nt4_dc:local)
[466(2350)/502 at 18m12s] samba.wbinfo_simple.authenticate=$DOMAIN/$DC_USERNAME%$DC_PASSWORD(nt4_dc:local)
[467(2351)/502 at 18m12s] samba.wbinfo_simple.allocate-uid(nt4_dc:local)
[468(2352)/502 at 18m12s] samba.wbinfo_simple.allocate-gid(nt4_dc:local)
[469(2353)/502 at 18m12s] samba.wbinfo_sids2xids.(nt4_dc:local)(nt4_dc:local)
[470(2354)/502 at 18m18s] samba.ntlm_auth.diagnostics(nt4_dc:local)(nt4_dc:local)
[471(2355)/502 at 18m18s] samba.ntlm_auth.(nt4_dc:local)(nt4_dc:local)
[472(2374)/502 at 18m20s] samba.wbinfo_simple.ping(nt4_member:local)
[473(2375)/502 at 18m20s] samba.wbinfo_simple.separator(nt4_member:local)
[474(2376)/502 at 18m20s] samba.wbinfo_simple.own-domain(nt4_member:local)
[475(2377)/502 at 18m20s] samba.wbinfo_simple.all-domains(nt4_member:local)
[476(2378)/502 at 18m20s] samba.wbinfo_simple.trusted-domains(nt4_member:local)
[477(2379)/502 at 18m20s] samba.wbinfo_simple.domain-info=BUILTIN(nt4_member:local)
[478(2380)/502 at 18m20s] samba.wbinfo_simple.domain-info=$DOMAIN(nt4_member:local)
[479(2381)/502 at 18m20s] samba.wbinfo_simple.online-status(nt4_member:local)
[480(2382)/502 at 18m20s] samba.wbinfo_simple.online-status.domain=BUILTIN(nt4_member:local)
[481(2383)/502 at 18m21s] samba.wbinfo_simple.online-status.domain=$DOMAIN(nt4_member:local)
[482(2384)/502 at 18m21s] samba.wbinfo_simple.check-secret.domain=$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) -> 98
samba3.smb2.notify(nt4_dc) -> 79
samba3.rpc.samr.passwords.lockout(nt4_dc) -> 61
samba4.rpc.echo on ncacn_np with object(nt4_dc) -> 60
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) -> 42
samba3.raw.lock(nt4_dc) -> 33
samba3.raw.search(nt4_dc) -> 33
ERROR: test failed with exit code 1