[Samba] wbinfo only lists one DC and idmap troubles

[Paul Leiber]

Hi,
>
>> Doesn't matter, if your Samba client is told to use a DC and that DC is
>> down,
>
> Told by whom?
> I expected at boot Winbind would look for the list of DCs, eventually 
> try to contact one and, if that fails, contact the other.
> (Which, BTW, I think it did, because that's what was listed and I saw 
> traffic from the client to the working DC).
>

I too was having issues with one specific client connecting to DCs, and 
was mentally preparing to contact this list for that reason. This thread 
rang a bell, that's why I jump in here.

In addition to the initial Samba AD DC ("DC1"), I installed a second 
Samba AD DC ("DC2") for redundancy reasons some time ago. The machine it 
was running on was broken, therefore DC2 was not responsive from time to 
time. I didn't make much of it, as I still had DC1 running.

One client ("Laptop") I joined to the domain after installing DC2 had 
issues to connect to the domain when DC2 was down. Other clients which 
had been joined to the domain prior to DC2 didn't have this issue. I 
started a thread some time ago on how to solve login issues with the 
Laptop member which would not connect. It turned out that the 
misbehaviour of the Laptop member was related to availability of DC2.

In the meantime, I replaced the hardware for DC2, and things are running 
quite smoothly now for the Laptop member.

However, I would expect that DC1 and DC2 are exchangeable and that any 
client would be running fine with either DC being online - that's the 
whole point of redundancy, right? But that doesn't seem to be the case. 
Unless there is some misconfiguration in my Samba settings (which were 
thoroughly vetted by Rowland in the other thread), there seems to be 
something fishy with the way a Samba domain member chooses between two DCs.

Paul