Hi.
I have a problem / understanding problem with Postfix.

I have set up three mailboxes.
They can send and get mails via getmail to the local mailbox.
For example, the mailboxes are ' thomas@mydomain.de', ' thomas@gmail.com', ' thomas@outlook.com'.
However, I cannot send mails to mailboxes other than those stored on the local server from the SAME domain.

As an example, thomas@mydomain.de cannot send to peter@mydomain.de.
And thomas@gmail.com cannot send to any gmail address other than itself.


I am also somehow aware of this, because the Postfix is responsible for the domains mydomain.de, gmail.com and outlook.com and wants to deliver them locally and can't find a mailbox for it.
(Remember, only the three Mailboxes I described above are stored on the mail server.)

Can I configure Postfix so that it only delivers the stored mail addresses locally and forwards all others to the Smarthost?

Maybe he is not responsible for domains but only for registered mail addresses?

How would one have to configure this correctly?

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I assume that this is an understanding problem, so I haven't sent any logfiles or configuration files yet, but I'm happy to do so if you wish.

Many thanks for any help.

No, you can only use ‘local domains’ that your host is responsible for.

If you don’t have a real domain, make a fake one for local use. Make sure it isn’t one that really exists.

Make as many local users as you want and configure getmail to deliver as appropriate.
You can also use aliases to cater for local delivery to those ‘real addresses’ without going off your server.

Hi.
Thank you so much for your answer.

So it is not possible to write to a domain for which the postfix is responsible if the mailboxes are not stored on the postfix?

For example, I have a single Gmail address that I pick up via getmail.
Unfortunately I can't send mails via Postfix to other Gmail addresses, because he is responsible for Gail.com but doesn't manage the other (external) mailboxes himself.


I simply didn't expect that. I had thought that I could determine, for example, about transport rules or something similar, to deliver one GMail address locally and to send all other GMail addresses via the Smarthost.
So that just doesn't work?