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dockerconstraintswildcarddocker-swarm

Docker swarm constraint wildcards

I am running a Docker swarm across 10 different host/servers/machines all labeled differently e.g. nginx_1 nginx_2 nginx_3 nginx_4 app_1 app_2 app_3 app_4 testing_1 testing_2

Using Docker swarm constraints is there a way to specify which node a service can run on using a label and wildcard which would tel the service to run on any node with a label starting with nginx e.g.

--constraint 'node.labels.name ==nginx*'
Solution

  • We can't use wildcards in --constraint for the time being.

    You could label all your nginx nodes with a new label, for instance:

    docker node update --label-add type=web node1
docker node update --label-add type=web node2
...

    And use --constraint to create your nginx service on web labeled nodes only:

    docker service create \
--name nginx \
--constraint 'node.labels.type == web' \
nginx