Self-hosted Sentry ships with a built-in outgoing SMTP server powered by exim4. The default configuration is set to use this server. All you need to do is to set a valid address for
mail.from setting in
config.yml and the FQDN of your Sentry instance for
.env. Keep in mind that if you start sending too many emails to public addresses, your new server may get marked as a spammer and banned.
If you want to use an external SMTP server you can set the relevant
mail.* settings in
config.yml file and ignore the built-in SMTP server. Refer to our email service documentation for all the details on what each setting means and does. If your MX records usually resolve to internal private network mail handlers, see this ticket for some pointers.