Cannot join UCS domain: "An unknown error with status code 502 occurred while connecting to the server, please try again later"

UCS - Univention Corporate Server
1

Hello,

I have an UCS master running, and now trying to join a UCS slave. I did a fresh install from iso, but get stuck at the step to join the UCS master. I gave ucs master IP address as the nameserver, chose the system role as “Domain controller slave”, the hostname of ucs master was correctly detected, entered user = Administrator, pass = pass of Administrator on ucs master.

I get the error “The connection to the UCS DC Master was refused. Please recheck the password”, which could be fixed by ensuring that ssh on master is running on standard port 22 and password authentication is allowed. After that the installer seems to do something when I clicked NEXT for a few mins and then gave the error

“An unknown error with status code 502 occurred while connecting to the server, please try again later”

I also tried to disable the firewall on ucs master (it’s running on a public VPS), same error.

Does someone have an idea what can I try to debug the problem?

Regards,
Tony

2

hello, tony2,
no solution from my end, but I confirm your problem. Our situation:
1 UCS master in AD compatible mode in site 7 (ver 5.02, fresh installation)
1 UCS backup DC in AD compatible mode in site 6 (ver 5.02, fresh installation)
Now, we plan to close site 6 and move to new site 5 and like to place the master there.

I already fail when trying to install DC in site 5 as backup DC. Error is also “502”.

In addition to this, I fail to login as Administrator on new DC in site 5.

The “big plan” was to install a UCS in site 5 as backup DC, migrate services and data, then decommission master in site 7 and promote site 5 using “backup2master”.
Is this supposed to work, or is there a recommendation for a better procedure?