Working on creating docker container in CoreOS oeparting system, could any one let me know how to assign new IP range for setting up docker bridge

Operating system team asking to assign new IP range to docker demon such that in CoreOS operating system created below files

-rw-r–r--. 1 root root 34 Mar 15 10:04 05-br0.netdev
-rw-r–r--. 1 root root 44 Mar 15 10:03
-rw-r–r--. 1 root root 107 Mar 15 10:01

mentioned required IP range , but unable to add bridge0 to

Machinename network # ip addr add dev bridge0
Error: an inet prefix is expected rather than “”.

noticed above error ,