Docker Swarm cheat sheet: Essential Commands and Tips

Introduction

Here’s a Docker Swarm cheat sheet to help you with common commands and operations:

Docker Swarm is a powerful tool for container management and application orchestration. For those working in the DevOps field, mastering Docker Swarm commands and techniques is essential for effective system deployment and management.

This article provides a detailed cheat sheet, compiling important commands and useful tips, to help you quickly master Docker Swarm and optimize your workflow.

The Docker swarm cheat sheet

Docker swarm Management

Set up master

docker swarm init --advertise-addr <ip>

How to Force the Manager on a Broken Cluster

docker swarm init --force-new-cluster -advertise-addr <ip>

Enable auto-lock

docker swarm init –autolock

Get a token to join the workers

docker swarm join-token worker

Get a token to join the new manager

docker swarm join-token manager

Join the host as a worker

docker swarm join <server> worker

Have a node leave a swarm

docker swarm leave

Unlock a manager host after the docker

docker swarm unlock

Print key needed for ‘unlock’

docker swarm unlock-key

Print swarm node list

docker node ls

Docker Service Management

Create a new service:

docker service create <options> <image> <command>

List the services running in a swarm

docker service ls

Inspect a service:

docker service inspect <service-id>

Scale a service (increase or decrease replicas)

docker service scale <service-id>=<replica-count>

Update a service:

docker service update <options> <service-id>

Remove a service:

docker service rm <service-id>

List the tasks of the service_name

docker service ps service_name

list running (active) tasks for a given service

docker service ps --filter desired-state=running <service id|name>

print console log of a service

docker service logs --follow <service id|name>

Promote a worker node to the manager

docker node promote node_name

The output terminal Promote a worker node to the manager as below

vagrant@controller:~$ docker node ls
ID                            HOSTNAME     STATUS    AVAILABILITY   MANAGER STATUS   ENGINE VERSION
9b2211c8l1bmhu3h2ij3kthxv *   controller   Ready     Active         Leader           20.10.14
0j0pslqf4g6xkki8ajydvc123     node1        Ready     Active                          20.10.14
f4cxubqg0wqdxsaj8pe4qsqlg     node2        Ready     Active                          20.10.14

vagrant@controller:~$ docker node promote f4cxubqg0wqdxsaj8pe4qsqlg
Node f4cxubqg0wqdxsaj8pe4qsqlg promoted to a manager in the swarm.

vagrant@controller:~$ docker node ls
ID                            HOSTNAME     STATUS    AVAILABILITY   MANAGER STATUS   ENGINE VERSION
9b2211c8l1bmhu3h2ij3kthxv *   controller   Ready     Active         Leader           20.10.14
0j0pslqf4g6xkki8ajydvc123     node1        Ready     Active                          20.10.14
f4cxubqg0wqdxsaj8pe4qsqlg     node2        Ready     Active         Reachable        20.10.14

Docker Stack Management

List running swarms

docker stack ls

Deploy a stack using a Compose file:

docker stack deploy --compose-file <compose-file> <stack-name>

Inspect a stack:

docker stack inspect <stack-name>

List services in a stack:

docker stack services <stack-name>

List containers in a stack:

docker stack ps <stack-name>

Remove a stack:

docker stack rm <stack-name>

Conclusion

You now have the Docker Swarm cheat sheet, which includes some of the most essential commands used in Docker Swarm.

For a more comprehensive list of options and additional commands, please refer to the official Docker documentation:

For a more detailed list of options and additional commands, you can refer to the official Docker documentation. I hope you find this helpful. Thank you for visiting the DevopsRoles page!