OpenDNS Linux IP Updater

Install ddclient

/etc/ddclient.conf

##
## OpenDNS.com account-configuration
##
protocol=dyndns2
use=web, web=myip.dnsomatic.com
ssl=yes
server=updates.opendns.com
login=opendns_username
password='opendns_password' # If there are any single-quotes in your password, put backslash ( \ ) before the single-quote to escape the character.
opendns_network_label #can find the network label in the Settings Tab of the OpenDNS Dashboard

https://support.opendns.com/hc/en-us/articles/227987727-Linux-IP-Updater-for-Dynamic-Networks