Issue

We have a problem with some of our users being able to log into one of our servers using Kerberos authentication with ssh. The same users do not have a problem when logging onto other servers and workstations at our facility. All systems are using the same Kerberos server and have identical /etc/krb5.conf files. A couple weeks ago our Kerberos database got corrupted and we had to restore it from backup. The common thread between the users that cannot log onto this one server using their Kerberos credentials is they were all created (Kerberos principles) after the Kerberos data base was restored. The database restore may or may not be connected to this problem but it does look suspicious.

Server having problems with Kerberos authentication:

Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: trying previously-entered password for 'user1', allowing libkrb5 to prompt for more 
Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: authenticating 'user1@DOMAIN.COM' to 'krbtgt/DOMAIN.COM@DOMAIN.COM'
Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: krb5_get_init_creds_password(krbtgt/DOMAIN.COM@DOMAIN.COM) returned 0 (Success)
Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: validating credentials  
Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: TGT failed verification using keytab and key for 'host/host1@DOMAIN.COM': Generic error (see e-text)            
Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: got result 0 (Success) 
Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: authentication fails for 'user1' (user1@DOMAIN.COM): Authentication failure (Success) 
Nov 13 08:50:43 host1 sshd[21834]: pam_krb5[21834]: pam_authenticate returning 7 (Authentication failure) 

The error would indicate there might be a problem with the keytab file or the host entry in the Kerberos database but if that were the case shouldn't it be a problem for anyone logging in using their Kerberos credentials on this server.