How to Change the Default Docker Network Address Allocation?

Question

How to change the default Docker network address allocation?

Environment

Container platform: Docker

Answer

You may experience setup test (connection) failures if your source or destination network overlaps with the default Docker network address range.

To change the default Docker network address pool, perform the following steps:

1. Stop the Hybrid Deployment Agent (if running):

   ./hdagent.sh stop
   

2. Remove unused networks:

   docker network prune
   

3. Update or create the daemon.json file with a new default address pool:

   • For rootful Docker, the file is in /etc/docker/.
   • For rootless Docker, the file is in ~/.config/docker/.

   Use the following template (modify the subnet to avoid overlap with your source or destination network):

   {
     "default-address-pools": [
       {
         "base": "192.168.0.0/16",
         "size": 24
       }
     ]
   }
   
   

   In this example, Docker will create networks from 192.168.0.0 to 192.168.255.0.

4. Restart the Docker service:

   • For rootful:

     sudo systemctl restart docker
     

   • For rootless:

     systemctl --user restart docker
     

5. Restart the Hybrid Deployment Agent:

   ./hdagent.sh start
   

6. Verify the network changes:

   docker inspect fivetran_ldp