[Samba] Samba domain name in short format

[Jeremy Allison]

On Mon, May 06, 2024 at 09:03:14PM +0000, Sun, Zhongdong via samba wrote:
>Hi Rowland,
>
>Thanks for your quick response.
>
>Yes, it's Samba+sssd+krb5+AD. So many technologies wrapped together,
> and I don't know which part can go wrong. We managed to make them work
>together with the full domain name format such as yu.yale.edu\zs24.
>But it didn't work with short format as YALE\zs24. When I did this
>in a Windows computer, it reported "We can't sign you in with this
>credential because your domain isn't available."
>This seems a DNS issue, because it cannot convert 'YALE' to its full name 'yu.yale.edu'.

Yep it's DNS. Client can't get a krb5 ticket for the server
as the full hostname isn't correct.