Error creating the default network "bridge": cannot create a network (docker0): conflicts with the network (docker0): networks have the same bridge name

Question

After stopping the docker, he refused to start again. He complains that another bridge called docker0 already exists:

level=warning msg="devmapper: Base device already exists and has filesystem xfs on it. User specified filesystem will be ignored." level=info msg="[graphdriver] using prior storage driver \"devicemapper\"" level=info msg="Graph migration to content-addressability took 0.00 seconds" level=info msg="Firewalld running: false" level=info msg="Default bridge (docker0) is assigned with an IP address 172.17.0.0/16. Daemon option --bip can be used to set a preferred IP address" level=fatal msg="Error starting daemon: Error initializing network controller: Error creating default \"bridge\" network: cannot create network fa74b0de61a17ffe68b9a8f7c1cd698692fb56f6151a7898d66a30350ca0085f (docker0): conflicts with network bb9e0aab24dd1f4e61f8e7a46d4801875ade36af79d7d868c9a6ddf55070d4d7 (docker0): networks have same bridge name" docker.service: Main process exited, code=exited, status=1/FAILURE Failed to start Docker Application Container Engine. docker.service: Unit entered failed state. docker.service: Failed with result 'exit-code'. 

Removing the bridge using ip link del docker0 and then launching the docker produces the same result with a different identifier.

Answer 1

The problem seems to be in /var/docker/network/ . There are many sockets that reference a bridge by its old identifier. To solve the problem, you can remove all sockets, remove the interface, and then start docker , but all your containers will refuse to work, as their sockets have disappeared. In my case, I do not care that my containers are apathetic, so this fixed the problem:

 ip link del docker0 rm -rf /var/docker/network/* mkdir /var/docker/network/files systemctl start docker # delete all containers docker ps -a | cut -d' ' -f 1 | xargs -n 1 echo docker rm -f # recreate all containers 

Answer 2

For me, I downgraded my OS (Centos Atomic Host in this case) and came across this error message. The senior Centos Atomic docker was 1.9.1. I used to have no docker boot containers or images.

I just ran below and the docker was happy again:

 sudo rm -rf /var/lib/docker/network sudo systemctl start docker 

Additional Information.