@bremner @xtaran indeed, sshsendmail is just a shim, i use it with #postfix and it works with #nullmailer as well... you could also use rsendmail (or plain sendmail) without sshsendmail but at this point, you have just a shell script that calls 'ssh remote sendmail "$@"', which i have done as well, but then is you have no local queue

One of my #GitLab instances was no longer able to send e-mails. (It tried to send almost empty e-mails, but its smarthost discarded those.)

It was the one that used #nullmailer as its #MTA. GitLab recommends either #Sendmail or #Postfix as an MTA. Switching to Postfix solved this issue for me.

Making sure that Postfix uses the #StartTLS capability of its smarthost took longer than expected.

It's also rather annoying that on Debian systems, postfix by default accepts connections from anywhere on the Internet even though I asked debconf to set up a “satellite system”.

When using Nullmailer, I just had to put the line “smtp.domain.tld smtp --port=25 --starttls” in /etc/nullmailer/remotes.

For Postfix, I need this:
inet_interfaces = loopback-only
smtp_tls_security_level = encrypt

Your mileage may vary.

Escribí algo sobre cómo reenviar los correos internos de un servidor GNU/Linux a nuestro buzón con #Nullmailer #GNU #Linux http://murana.uy/enviar-el-correo-de-nuestro-servidor-con-nullmailer/