Unable to Join Slave to Domain



Hey there, I’m having an issue joining a third slave controller to my UCS domain.

I use the following command to join:

univention-join -dcname $MasterDC -type domaincontroller_slave
Enter DC Master Account : administrator
Enter DC Master Password: $AdministratorsPW

The log file: /var/log/univention/join.log shows the following

* Join failed!                                                           *
* Contact your system administrator                                      *
* Message:  Please visit https://help.univention.com/t/8842 for common problems during the join and how to fix them -- The ssh-login to Administrator@$MasterDC failed with " ". Please make sure the account Administrator exists and is a member of the Domain Admins group!
Wed Sep 12 13:59:23 PDT 2018: finish /usr/sbin/univention-join
Wed Sep 12 14:00:58 PDT 2018: starting /usr/sbin/univention-join -dcname $MasterDC -dcaccount Administrator -dcpwd /tmp/tmpeT9Jrn

I checked the article mentioned in the log https://help.univention.com/t/8842

The SRV record returns correctly when queried from the slave attempting to join (The master DC is nameserver1 in UCR)

The slave can also ping the master by IP and FQDN and I can also SSH into the Master DC from the slave using the administrator account and password.

UCS version on the master and the slave is both 4.3-2 errata234 (Neustadt)

Any ideas? I’m still poking around in various logs to see if I can figure out what’s going on here.



I forgot to mention that the Administrator account is indeed a part of the Domain Admins group


Reinstalled slave DC with exact same configuration but joined before updating (4.3-1 errata112) and it worked…

Not sure if it’s something wrong in the newer version or if setting up a slave DC, updating and then joining isn’t supported.

Going to try updating now and see if it still functions correctly.


In general the DC Master must always have the most recent UCS version installed of all the UCS servers in a domain. This not only affects updating (you must always update the DC Master first, all other UCS servers afterwards), but also the join process.


Thanks for the reply! Just to elaborate, the Master and joining slave were on the exact same version and errata when the join was attempted.