I see that in one tutorial online there are at least 2. 0 mail mail.mydomain.com 10 mail mail.mydomain.com why are there multiple dns entries here? How many should a webhosting/mail server have? What is the point of having dual entries for same mail server? Wouldnt this normally be for pointing at a backup mail server in the event primary one goes down?
Code: 0 mail mail.mydomain.com 10 mail mail.mydomain.com you don't need to MX with a different priority for the same hostname.
MX record can be added per your requirements but the priority play an important role.The lower value has the highest priority like 0 has the highest priority.
