How to specify Container deployment Node in docker swarm Cluster
This article introduces how to specify container deployment nodes in docker swarm cluster. The content is very detailed. Interested friends can use it for reference. I hope it will be helpful to you.
In docker swarm clusters, containers are usually deployed randomly to each node by default. However, it is sometimes encountered in deployment that some services are specified on a special machine.
If this happens, we can take advantage of the deploy.placement.constraints attribute in the docker-compose.yml file
1. Specify a manager or work node
Deploy: replicas: 1 placement: constraints: # # commonly used to specify manager or work nodes-node.role = = worker
two。 Specify hostname
Deploy: replicas: 1 placement: constraints:-node.hostname = = docker1
3. Specify node label
Node label can label one or more machines, and then specify the node tag in the compose file, which can be deployed on the machine with the corresponding tag. The specific steps are as follows:
Now label all the node machines on the master node machine, and the command is as follows:
Docker node update-- label-add role= tag name hostname for example, I'm going to label a machine with the hostname docker1 with the label db docker node update-- label-add role=db docker1.
Then, configure the compose file
Deploy: replicas: 1 placement: constraints:-node.labels.role = = db
Commands to delete node tags
Docker node update-- label-rm role tag name
4. Specify node id
Check the id of node first, and the command is as follows:
Docker node ls
As shown in the figure:
Deploy: replicas: 1 placement: constraints:-node.id = = xy4ttvg3xqbvwu4lok2xpgmrc
5. According to the engine tag
Deploy: replicas: 1 placement: constraints:-engine.labels.operatingsystem==ubuntu 14.04 so much about how to specify container deployment nodes in the docker swarm cluster. I hope the above content can be helpful to you and learn more. If you think the article is good, you can share it for more people to see.
