Custom Docker Bridge Network

[#1]

At times customers want to change the default docker bridge network.  Perhaps their monitoring software utilizes that range for example.  The following illustrates the default IP range for docker0

# ip a show docker0
5: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default
link/ether 02:42:be:4d:f3:e7 brd ff:ff:ff:ff:ff:ff
inet 172.17.0.1/16 scope global docker0
valid_lft forever preferred_lft forever

CDSW does not use the docker0 bridge within CDSW and this interface is down. To change it however a customer may create a daemon.json file in order to create a custom docker0 range.  Documentation on that is enclosed below.

- https://docs.docker.com/v17.09/engine/userguide/networking/default_network/custom-docker0/

/etc/docker/daemon.json
{
"bip": "192.168.1.5/24",
"fixed-cidr": "192.168.1.5/25"
}

Thereafter you would stop docker on all nodes and ensure the Docker daemon is up and ifconfig shows the right values for the docker0 interface. Once this is verified you can start CDSW again.