Sendmail configurationΒΆ
Enable access to the sendmail server from containers on the host. Find and edit /etc/mail/sendmail.mc accordingly to make it listen on the docker network and enable the relay:
DAEMON_OPTIONS(`Port=smtp,Addr=172.18.0.1, Name=MTA')dnl
FEATURE(`relay_based_on_MX')dnl
Grant relay access from the docker container network editing /etc/mail/access, e.g.:
Connect:localhost.localdomain RELAY
Connect:localhost RELAY
Connect:127.0.0.1 RELAY
Connect:172 RELAY