How to forward messages on postfix to external domains?

Question

linux

There is a working bunch of postfix+dovecot+postfixadmin. There is a need to set up mail forwarding to another domain, that is, when receiving a letter to the [email protected] mailbox, the forwarding went, for example, to [email protected], but it is necessary to replace smtp.mailfrom with [email protected]
I tried to do postfixadmin through aliases, but the mail leaves with smtp.mailfrom the source mailbox. That is, sent from [email protected] from him and flew to gmail.com, and accordingly there is a problem with checking SPF, DKIM, DMARC.
I read the docks and forums, including the postfix documentation, but I did not understand how to organize the required scheme.
Thanks to all!

Answer 1

Have you read www.postfix.org/ADDRESS_REWRITING_README.htm?
I didn't check it, but, in theory, everything is simple here:
/etc/postfix/main.cf:
sender_canonical_maps = hash:/etc/postfix/sender_canonical
/etc/postfix/sender_canonical:
@ya.ru @lada.ru
postmap /etc/ postfix/sender_canonical
service postfix reload