[Samba] Some Ubuntu stations can't logon when I upgraded Samba DC

[Denis Morejon]

Hi:

I have two DCs with debian 10 and Samba 4.7.4 working find. In my 
network, I have different OSs workstations: W7, W10, Ubuntu and Mint.

They have been log-in every day without problem. And samba-tool dbcheck 
returns no error on both DCs.


As the Samba version is too old, I wanted to upgrade first from 4.7.4 to 
4.7.12 using the source code.

./configure

make

make install

Just as I did last time I compiled the  4.7.4.

I stopped Samba on both DCs, compiled the new version (4.7.12) with no 
error on both DCs.

Then I started Samba on both DCs and typed this on DC1:

  samba-tool dbcheck --cross-ncs --fix

This time some objects were fixed automatically.

I ran this command in the second DC too.

I typed this command for the second time and It returned 0 error.

I restarted Samba service on both DC without problems.

But, as result, some Ubuntu workstations couldn't logon again

The user's password was right because we have a web to probe users using ldap. Even, we logon the user
on other Windows machines and they logon ok.

What should be happening ?