How to set up masquerading in sendmail?

Question

linux

Hello! After installing sendmail, I still can't send emails, the error
"Sender address rejected: Domain not found" is written in the logs - here I already realized the problem is that he is trying to send from some soap that does not exist (although I don’t understand where it comes from is taken). I decided to prescribe another soap through masquerading ... and once these settings were picked up and the letter arrived! But after that it just stopped. What could be the reason? Maybe something else needs to be added? ..
contents of sendmail.mc :

MAILER_DEFINITIONS
MAILER(`local')dnl
MAILER(`smtp')dnl
MASQUERADE_AS(`домен.ru')
MASQUERADE_DOMAIN(`домен.ru')
FEATURE(`allmasquerade')
FEATURE(`masquerade_entire_domain')
FEATURE(`masquerade_envelope')
FEATURE(`always_add_domain')

Answer 1

FEATURE(allmasquerade)
FEATURE(masquerade_envelope)
FEATURE(local_no_masquerade)

MASQUERADE_AS(`deltahw.ru')

This is usually enough. local_no_masquerade can be omitted if there is no other local server in the DMZ.
I hope the above is a piece of sendmail.mc, and not the whole one - because if it's all of it, then it won't work :)