[Samba] Proper server DNS naming

[Łukasz Sellmann]

Hi

I'm trying to connect my actual mail server as member to samba AD
environment . Purpose is to be able to use kerberos auth with dovecot.

The question is how to proper set up dns names with this scenario.
Now my REALM is office.domain.com, the main DC is named
dc1.office.domain.com.
My mail server witch is not connected to AD has FQDN mail.domain.com and
it's visible from internet side and for lan clients as mail.domain.com
As i understand for domain join purposes it should be visible in AD
environment as mail.office.domain.com.
Would be ok to just set in /etc/hosts on mail server to point for its ip
both names mail.office.domain.com and mail.domain.com ?
What hostname i should set for system in /etc/hostname , just mail as name ?

I want to avoid inconsequent naming in my environment, but don't want to
change name of actual mail server, users have been using it as
mail.domain.com

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Regards Lukasz