Comment 2 for bug 1576799

I don't think this is a regression. The Samba security update is now more strict when validating TLS certs.

I'm not sure why it's using the ip address instead of the hostname, that's probably a configuration issue.

If you want a workaround, you can try adjusting cert checking, see:

https://wiki.samba.org/index.php/Samba_4.3_Features_added/changed#tls_verify_peer_.28G.29