how to choose an appropriate Droplet hostname for LAMP and Sendmail/Postfix with multiple domains?
I initially set my droplet name to ‘my-first-droplet’, not knowing really what the implications would be. I am successfully hosting 4 domains on the same droplet using LAMP/https/virtualhost configurations. However I am failing to implement Sendmail/Postfix for sending mail via PHP. I suspect that my Droplet’s hostname is causing this, as configuring mail asks for a FQDN, which my droplet’s is not really a valid FQDN.
How can I choose an appropriate hostname and setup sendmail/postfix for my droplet when I have 4 domains, each not taking priority over another so picking 1 for the hostname seems inappropriate. Is hosting several domains in 1 droplet even recommended?