Recently I ran into an interesting "issue" where a user's cron job wouldn't work and restarting the cron daemon did no good. Having checked the
/etc/cron.allow and
/etc/cron.deny files, I found nothing relevant, and so I Googled the error found in
/var/log/messages:
Apr 9 12:31:01 server crond[8993]: Authentication token is no longer valid; new one required.
No password was necessary for this account, so to the system, it was a "locked" account, whereas to me, it was a service account.
[root@server ~]# grep username /etc/shadow
username:!!:13306:0:90:14:::
Setting a password resolved this.
