<html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body text="#000000" bgcolor="#FFFFFF"> Hi there I am a bit confused on how to est the hostname on an 18.04 server. I intend to use the server as a mail server running iRedMail. The instruction to set up iRedMail instructs to set : <p style="margin-bottom: 4px; padding: 0px; font-size: 17px; line-height: 24px; color: rgb(0, 0, 0); font-family: "PT Sans", Georgia, Palatino, serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">On Debian/Ubuntu Linux, hostname is set in two files: <code style="font-family: Consolas, Monaco, "Andale Mono", monospace; line-height: 25px; font-size: 14px; background: rgb(245, 245, 245); border: 1px solid rgb(204, 204, 204); border-radius: 2px; padding: 1px 5px; overflow-wrap: normal;">/etc/hostname</code> and <code style="font-family: Consolas, Monaco, "Andale Mono", monospace; line-height: 25px; font-size: 14px; background: rgb(245, 245, 245); border: 1px solid rgb(204, 204, 204); border-radius: 2px; padding: 1px 5px; overflow-wrap: normal;">/etc/hosts</code>. <ul style="padding-left: 30px; margin: 0px; font-size: 17px; line-height: 24px; color: rgb(0, 0, 0); font-family: "PT Sans", Georgia, Palatino, serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"> <li style="line-height: 26px;"><code style="font-family: Consolas, Monaco, "Andale Mono", monospace; line-height: 25px; font-size: 14px; background: rgb(245, 245, 245); border: 1px solid rgb(204, 204, 204); border-radius: 2px; padding: 1px 5px; overflow-wrap: normal;">/etc/hostname</code>: short hostname, not FQDN.</li> </ul> <pre style="padding: 5px 10px; white-space: pre-wrap; background: rgb(245, 245, 245); border: 1px solid rgb(204, 204, 204); border-radius: 2px; overflow-wrap: normal; font-size: 14px; line-height: 25px; margin-left: 30px; color: rgb(0, 0, 0); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"><code style="font-family: Consolas, Monaco, "Andale Mono", monospace; line-height: 25px; font-size: 14px; background: rgb(245, 245, 245); border: 0px; border-radius: 2px; padding: 5px 10px 5px 0px; overflow-wrap: normal; margin: 0px;">mx</code></pre> and to to set etc hosts: <ul style="padding-left: 30px; margin: 0px; font-size: 17px; line-height: 24px; color: rgb(0, 0, 0); font-family: "PT Sans", Georgia, Palatino, serif; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"> <li style="line-height: 26px;"><code style="font-family: Consolas, Monaco, "Andale Mono", monospace; line-height: 25px; font-size: 14px; background: rgb(245, 245, 245); border: 1px solid rgb(204, 204, 204); border-radius: 2px; padding: 1px 5px; overflow-wrap: normal;">/etc/hosts</code>: static table lookup for hostnames. Warning: Please list the FQDN hostname as first item.</li> </ul> <pre style="padding: 5px 10px; white-space: pre-wrap; background: rgb(245, 245, 245); border: 1px solid rgb(204, 204, 204); border-radius: 2px; overflow-wrap: normal; font-size: 14px; line-height: 25px; margin-left: 30px; color: rgb(0, 0, 0); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;"><code style="font-family: Consolas, Monaco, "Andale Mono", monospace; line-height: 25px; font-size: 14px; background: rgb(245, 245, 245); border: 0px; border-radius: 2px; padding: 5px 10px 5px 0px; overflow-wrap: normal; margin: 0px;"># Part of file: /etc/hosts 127.0.0.1 mx.example.com mx localhost localhost.localdomain </code></pre> so what I did: in /etc/cloud/cloud.cfg I changed: # This will cause the set+update hostname module to not operate (if true) preserve_hostname: true in /etc/hostname: mx in /etc/hosts: 127.0.1.1 redcor.com redcor.com 127.0.0.1 mx.redcor.com localhost # The following lines are desirable for IPv6 capable hosts ::1 ip6-localhost ip6-loopback fe00::0 ip6-localnet ff00::0 ip6-mcastprefix ff02::1 ip6-allnodes ff02::2 ip6-allrouters ff02::3 ip6-allhosts However when I execute: hostname -f I get: mx How should I setup the hostname, that I can use the server as a mailserver for mail.redcor.com thannks, robert </body> </html>