[Samba] ntlmssp_server_postauth: invalid NTLMSSP_MIC on CTDB fileserver (NT-style domain)

Alex Crow acrow at integrafin.co.uk
Thu Sep 22 09:58:18 UTC 2016

Hi List,

As the subject states, I'm running a CTDB cluster. Samba is Sernet 4.4.5
in an NT-Style Samba domain (DCs are Centos 6 packaged samba, 3.6.22)

Every so often, users are unable to connect to network shares. Most of
the problems seem to happen on Windows 7 domain members, but smbclient
will also fail to connect. I see these lines in the logs for every
attempted connection:

[2016/09/22 06:08:42.135972,  1]
  ntlmssp_server_postauth: invalid NTLMSSP_MIC for user=[aa3]
domain=[FOO_NET] workstation=[VM-FOOBAR]
[2016/09/22 06:08:42.135995,  1] ../lib/util/util.c:559(dump_data)
  [0000] F1 27 49 D5 8E 68 FE 25   B7 6E C9 7C 86 F7 D9 21   .'I..h.%
[2016/09/22 06:08:42.136013,  1] ../lib/util/util.c:559(dump_data)
  [0000] BA 8D 1F 5E A8 7D 9D 5E   7B 05 4D C4 BD 30 EE 72   ...^.}.^

smbclient -L seems only to work as a guest at this point, but testing it
with an authenticated user fails with the same messages.

The only way to fix this seems to be to restart the CTDB daemon on all
the servers.

Anyone have any insight into what might be causing this?



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