Use inadyn to update dyndns automatically on Ubuntu

1. install inadyn client

sudo apt-get install inadyn

2. create the configuration file

sudo vi /etc/inadyn.conf

--username username
--password password
--update_period 60000
--alias myhost.dyndns.org
--background

3. set automatic update on boot

sudo crontab -e


@reboot /usr/sbin/inadyn