Task

In RancherOS v1.5.x the docker0 bridge network has a default IP range of 172.17.0.0/16 and the docker-sys bridge for system-docker has a default range of 172.18.0.0/16. This article details how to update these ranges.

Pre-requisites

• A RancherOS v1.5.x host

Resolution

The docker0 bridge range is set by the rancher.docker.bip argument, whilst the docker-sys bridge is set by rancher.system_docker.bip argument.

These can be configured in the cloud-config as follows:

rancher:
  docker:
    bip: 192.168.0.0/16
  system_docker:
    bip: 172.19.0.0/16

These can also be customized after the host has started with the ros config command, and will take effect after a reboot:

ros config set rancher.docker.bip 192.168.0.0/16
ros config set rancher.system_docker.bip 172.19.0.0/16

Further reading

You can read more on configuring Docker or System Docker within the RancherOS documentation.