Today I had several filers at different OS levels stop serving data via CIFS with the following errors. I had to stop and restart CIFS to get CIFS working properly. The filer acted as if its kerberos ticket wasn't valid with any of the domain controllers. Has anyone seen this before?

Cifs domain info command:

Not currently connected to any DCs
Preferred Addresses:
                          None
Favored Addresses:
                          ip            WNTNABO2         PDCBROKEN
                          ip    WNTNABO1         PDCBROKEN
Other Addresses:
                          ip   WNTNABO4         PDCBROKEN
                          ip    WNTNACRUBO1      PDCBROKEN

/etc/messages output:

Thu Jan 26 15:03:35 MST [cifs.trace.GSS:error]: AUTH: Unable to acquire filer credentials: (0x96c73a44) KRB5 error code 68.

Thu Jan 26 15:03:35 MST [cifs.server.infoMsg:info]: CIFS: Warning for server \\WNTNANI: Connection terminated.
Thu Jan 26 15:04:07 MST [auth.dc.GetDCName.failed:error]: AUTH: Error 0x0 while trying to get Domain Controller name for

Thu Jan 26 15:04:32 MST [sshd_0:info]: Did not receive identification string from x.x.x.x
Thu Jan 26 15:04:39 MST [auth.dc.GetDCName.failed:error]: AUTH: Error 0x0 while trying to get Domain Controller name for

Thu Jan 26 15:05:11 MST [auth.dc.GetDCName.failed:error]: AUTH: Error 0x0 while trying to get Domain Controller name for .

Thu Jan 26 15:05:43 MST [auth.dc.GetDCName.failed:error]: AUTH: Error 0x0 while trying to get Domain Controller name for

Thu Jan 26 15:07:01 MST [sshd_0:info]: Did not receive identification string from x.x.x.x
Thu Jan 26 15:09:32 MST [sshd_0:info]: Did not receive identification string from x.x.x.x

Any insight into this would really help me out. I have a case open with Netapp as well.

-Mark