TODO: develop procedure for renaming the volume group and document here (when / is on LVM as ours normally are, this may require rebuilding the initial RAM disk, re-configuring the boot manager, editing fstab ...). Maybe useful links: https://we.riseup.net/debian/renaming-a-lvm-root-volume-group, https://bugzilla.redhat.com/show_bug.cgi?id=230190#c17 (RedHat),
TODO: is any postfix re-configuration required?
Reference: Debian WIKI page on changing hostname.
As root either run netconfig
(full prompted re-configuration requiring IP addresses and domain name) or do it the manual way by editing:
then run /bin/hostname $(cat /etc/HOSTNAME | cut -f1 -d .)
If running or using any of avahi, CUPS, ejabberd, Exim, /etc/motd, OpenSSH server, ssmtp or sysklogd then read the Debian WIKI page on changing hostname
service hostname restart
Not tested (may all be done by the commands above): if running or using any of avahi, CUPS, ejabberd, Exim, /etc/motd, OpenSSH server, ssmtp or sysklogd then read the Debian WIKI page on changing hostname.
There will also be references to the old hostname in /etc/postfix/generic and /etc/postfix/main.cf:
postconf -e myhostname=<hostname>
Obvisouly replace <hostname> and <domain> by the appropriate values
On DNS servers which have record(s) for the old name, change both the forward and reverse data files.
When the hostname of a system on the Blue Light LANs (192.168.10.0 and 192.168.28.0) is changed, the DNS service on backupserver will need re-configuring as documented in DNS server (bind) administration.
On computers with an /etc/hosts file which has record(s) for the old name, change the line.