Block network removal with existing task-attachment (via --attachable) #1692
Description
swarmkit prevents any attempt to remove a network with an attached service. We should also provide a similar functionality for attached tasks.
madhu@Ubuntu-vm docker (npv2) $ sudo docker network create -d overlay --attachable mhnet
8lp3i90vvdoydz4rj1qttqtya
madhu@Ubuntu-vm docker (npv2) $ sudo docker network ls
NETWORK ID NAME DRIVER SCOPE
9856e7dac0b7 bridge bridge local
90775a09f418 docker_gwbridge bridge local
2fdd8797dd07 host host local
6jfzejzselnv ingress overlay swarm
8lp3i90vvdoy mhnet overlay swarm
908854bcd94f none null local
madhu@Ubuntu-vm docker (npv2) $ sudo docker run --net=mhnet --net-alias=c1 --name=cont -itd busybox sh
b8e69ade126b7d448281bc6e8cc2dc1a6c929c49d9ad12578075d007300c111a
madhu@Ubuntu-vm docker (npv2) $ sudo docker network rm mhnet
mhnet