We currently have a single mail server (RHEL/sendmail) for all mail "mail.example.com". We have added a second mail server "email.example.com". We intend to use this for bulk email, while "mail.example.com" remains for transaction and internal mail.
We have DKIM set up for "mail.example.com", but I need to set up DKIM for "email.example.com".
My question is this: Can I use the same TXT record I have for "mail.example.com" for "email.example.com" and modify some DKIM/milter/sendmail settings? Or do I have to create an entirely seperate TXT record and key.
Best Answer
You can reuse the same records and keys for the new server. It's best practice to setup new keys and records for each server however; any compromise on a single server leaves the others unaffected.