Setting it up on ubuntu with Namecheap

This guide assumes that you have an account on Namecheap already with a domain and dynamic DNS enabled.

1. Install ddclient: sudo apt install ddclient
2. No need to fill out properly the forms while setting it up, we will change the configuration files anyway
3. It will create two files based on what you chose/entered during setup: /etc/ddclient.conf and /etc/default/ddclient
4. First let's edit sudo nano /etc/ddclient.conf with the following configuration:

   use=web, web=https://dynamicdns.park-your-domain.com/getip
   protocol=namecheap
   server=dynamicdns.park-your-domain.com
   login=your.domain
   password=your DDNS password
   @ # Updates your domain, you can also use the wildcard character "*" that will update all your domain
   

5. Now let's edit sudo nano /etc/default/ddclient
   1. Set run_daemon to true
   2. and daemon_interval depending on how frequently you want ddclient to check and update your IP

      # Configuration for ddclient scripts
      # generated from debconf on Thu Jun  9 20:42:11 CEST 2022
      #
      # /etc/default/ddclient
      
      # Set to "true" if ddclient should be run every time DHCP client ('dhclient'
      # from package isc-dhcp-client) updates the systems IP address.
      run_dhclient="false"
      
      # Set to "true" if ddclient should be run every time a new ppp connection is
      # established. This might be useful, if you are using dial-on-demand.
      run_ipup="false"
      
      # Set to "true" if ddclient should run in daemon mode
      # If this is changed to true, run_ipup and run_dhclient must be set to false.
      run_daemon="true"
      
      # Set the time interval between the updates of the dynamic DNS name in seconds.
      # This option only takes effect if the ddclient runs in daemon mode.
      daemon_interval="60"
      

6. Test your configuration: sudo ddclient
   
   1. You should see something like: SUCCESS:  updating @: good: IP address set to X.X.X.X
7. Restart ddclient and check its status to see if everything is properly:
   1. sudo service ddclient restart
   2. sudo service ddclient status
8. If you get a warning/error about the cache, simply delete the file and restart ddclient
   1. sudo rm /var/cache/ddclient/ddclient.cache
   2. sudo service ddclient restart