This page explains how to change a system's hostname (i.e rename a computer/server)

Executive summary: hostname(1) isn't enough.

Rename a computer

Core networking

Update /etc/hostname
Update /etc/hosts, so local address(es) resolves with the new system name.
Reload the network configuration. You have two options
- Reload configuration files
  This will temporarily disconnect your system from the network (ssh usually resists short disconnection)
```
invoke-rc.d hostname.sh start
invoke-rc.d networking force-reload
invoke-rc.d network-manager force-reload
```
  ToDo: is it useful to reload network-manager?
- or the lazy way: Restart the system.

Application specific

avahi

Avahi is used to publish (announce) local services. If you tweaked /etc/avahi/* you should run:

```
invoke-rc.d avahi-daemon force-reload
```

ssmtp

Ssmtp is a light weight, send-only smtp server.

Adjust /etc/ssmtp/ssmtp.conf (hostname=, etc.). You don't need to restart the service.

Exim

Adjust /etc/exim4/update-exim4.conf.conf (hostname=). You need to restart the service.

Message Of The Day

Adjust /etc/motd. You don't need to restart a service.

Cups

Adjust /etc/printcap . You need to restart the service.

Mailname

Adjust /etc/mailname. You don't need to restart the service.

Openssh server

Adjust /etc/ssh/ssh_host_rsa_key.pub and /etc/ssh/ssh_host_dsa_key.pub (root@hostname at the end). You need to restart the service.

other

(to be written) there must be others...
Charlie: It was me who took you. Not the Others...

Idea of script to help you on

Complexe or unusual ancient hostname

#!/bin/bash usage() {
- echo "usage : $0 nouveau_nom_hote" exit 1
}
[ -z $1 ] && usage
ancien=hostname nouveau=$1
grep $ancien /etc/ -rl 2>/dev/null | while read file do
- sed s:$ancien:$nouveau:g $file > ${file}.tmp mv ${file}.tmp $file
done

See also

hostname(1), hostname(7)
?Howto Clone a System - system unique identifiers, to be changed when cloning a system.