SSSD - sudo authentication fails with '4 (System error)'

There is this strange error where sssd allows logins using gssapi but does not permit sudo and instead writes the dreaded '4 (System error)' to /var/log/secure:

 Sep 7 10:48:30 server sudo[676183]: pam_sss(sudo:auth): authentication failure; logname=archy uid=103600028 euid=0 tty=/dev/pts/0 ruser=archy rhost= user=archy  
 Sep 7 10:48:30 server sudo[676183]: pam_sss(sudo:auth): received for user archy: 4 (System error)

In my case, it was old kerberos tickets that were not deleted. So The fix should be really simple:

 [archy@server ~]$ kdestroy -A  
 [archy@server ~]$ kinit

Troubleshooting steps that might be of interest might be the date / time, hbac rules and the sssd-cache.

 [root@server ~]# sudo sssctl cache-expire -E  
 [root@server ~]# sudo systemctl restart sssd.service

Feel free to comment and / or suggest a topic.

Comments

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