What does this mean "relay this domain"

fiedin

Hi
I want to understand this 3 option here

What does these 3 box means? what does it do if i click them on.

Relay this domain
Relay all recipients
↪ If you choose not to relay all recipients, you will need to add a (“blind”) mailbox for every single recipient that should be relayed.

Relay non-existing mailboxes only. Existing mailboxes will be delivered locally.

esackbauer

Relay means: Receive mails for that domain. But then send them somewhere else.

“Relay this domain” will receive any mails for that domain and send them further on to either the mailserver it finds in the MX record or use a defined sender dependent transport. Regardless if there is a mailcow user with a defined mail address.

“Relay all recipients” will only relay existing mail addresses defined in mailcow.

“non-existing Mailboxes” is the opposite, only non-existing mail addresses of that domain will be relayed.

fiedin

esackbauer
thanks for the reply.

so is it like we put a parked domain inside mailcow and send them somewhere else? like forwarding?

zx1100e1

esackbauer Can you clarify what a “Blind mailbox” is, and/or how to define one?

ecdlguy

esackbauer I’ve got a question regarding “Relay this domain”: If a mailcow host receives a mail, the mailcow host must be among the MX records. So if “Relay this domain” sends the mail further on to a mailserver it finds in the MX record, it would relay it to the very same mailcow host?

esackbauer

I haven’t tried that. But usually this is used if you have more than one mail server in your organisation e.g. new mailcow and old exchange. Having still all users on exchange but using mailcow for MX already, then you would need this, as preparation for the actual migration.

ecdlguy

esackbauer Maybe the option makes no sense without specifying a transport map. Otherwise the option would probably lead to a mail loop.

esackbauer

If you have an internal DNS which has a MX record for the Exchange server as per my example, then you dont need a transport map. It all depends on your network landscape.

ecdlguy

Yes that’s true. Thanks!