I an running CentOS7 in a docker container. I need to send email from that container so I installed sendmail and then I run: m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf` and when I try and send mail it fails with: larry.martll at gmail.com... Connecting to [127.0.0.1] via relay... larry.martll at gmail.com... Deferred: Connection refused by [127.0.0.1] Anyone know how I can configure sendmail so that I can send mail?