After stopping docker it refused to start again. It complaint 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'.
Deleting the bridge with ip link del docker0
and then starting docker leads to the same result with another id.