How to understand the reason for non-signing of DKIM messages?

Question

postfix

The people, I was engaged in a mail server. I'm trying to put OpenDKIM on a PostFix server, but mail-tester.com keeps saying that there is no signature. Team

opendkim-testkey -d domen.ru -k /etc/dkimkeys/domen.ru.private -s domen.ru -vvv

returns

opendkim-testkey: using default configfile /etc/opendkim.conf
opendkim-testkey: key loaded from /etc/dkimkeys/domen.ru.private
opendkim-testkey: checking key 'domen.ru._domainkey.domen.ru'
opendkim-testkey: key not secure
opendkim-testkey: key OK

Also, all services that ask you to enter a domain and a selector for verification give a positive result. One of them:

What am I doing wrong? Maybe dig into the Postfix settings?

Answer 1

what does the id postfix command show?