If using DHCP on Ubuntu to populate your network configuration, there can be times when customising the DNS information can seem a little difficult.
In my case, the DHCP server was supplying my desktop /etc/resolv.conf with the DNS information:
nameserver a.b.c.d nameserver a.b.c.e domain example.com search example.com
This file gets auto-generated every time the NetworkManager restarts the interface, so there’s no point editing it by hand.
The problem was, I was mostly using servers in the subdomain “dev.example.com”, and wanted this added to the search list, so I didn’t have to type the “.dev” in every time. I’m lazy like that.
The fix is to edit
sudo vi /etc/dhcp/dhclient.conf
and add the following line:
append domain-search "dev.example.com";
Then, restart the dhclient process to update:
# pkill -HUP dhclient
The network interface will bounce, and when it comes back up, the extra domain-search “dev.example.com” will have been added to /etc/resolv.conf
To add extra domains to the search path, just add extra “append” lines.
Matt Parsons is a freelance Linux specialist who has designed, built and supported Unix and Linux systems in the finance, telecommunications and media industries.
He lives and works in London.