How to receive email from another domain using cname?

Question

For example,

I have an address [email protected]. I want to send email to this address and receive it on [email protected] or [email protected].

Is it possible to do this trick without configuring redirect of emails? For example, with cname.

Answer 1

Ask the administrator of the first email address to setup a forwarding to the second one. This can be done address by address. On Unix it starts often by a simple .forward file in home directory.

You are stating you do not want forwarding, but why exactly? Because if you intend to do DNS changes (that will only partially solves the problem as @HomoTechsual shows) that means you control example1.example in some way (otherwise you won't be able to do any DNS change here), so if you control it why you do not want to set up forwarding on it?

By being so overly generic in your question, you are making it difficult to give you relevant answers, so you probably need to edit your question to be more specific/clear on your constraints. Using non obfuscated names could help too.

Answer 2

You can't do this purely with DNS due to how email routing works. The destination email server would need to know that it is supposed to handle mail for both/all domains and to route these emails to the same mailbox (either through use of aliases or forwarding)

Email is generally routed through "Mail Exchange" or MX records in DNS falling back to A/AAAA records where MX records aren't configured.

The scenario is thus:

• You send an email to [email protected]

• Your MX record for mail.example1.example says deliver mail to mail.example2.example

• Your outgoing mail server resolves mail.example2.example to 192.0.2.111

• Your outgoing mail server says to 192.0.2.111 I have an email here for [email protected]

Here one of two things happens:

1. 192.0.2.111 says "Sorry I don't know how to handle mail for mail.example1.example, goodbye."
2. 192.0.2.111 says "Ah okay, thanks" and delivers the email according to it's configured aliases or forwarders.

Note: This is drastically oversimplified but the key point is that you cannot forward mail to a different domain without configuring the receiving mail server accordingly. Just changing the DNS is very unlikely to work with a sanely configured receiving mail server.