Swarm Synchronous Services

Introduction

Synchronous service create and service update

A nice PATCH has been merged into Docker a few minutes ago that allows
service creations and updated to be executed synchronously.

Creating a synchronous service

Initialize your swarm

docker swarm init --advertise-addr eth1

Create a new synchronous serivce using the new -d flag

docker service create -d=false --name top --replicas 5 busybox top

You should an output similar to the following in the terminal:

mmsdrpbigre7ls9vp6mhig3vz
overall progress: 5 out of 5 tasks
1/5: running   [==================================================>]
2/5: running   [==================================================>]
3/5: running   [==================================================>]
4/5: running   [==================================================>]
5/5: running   [==================================================>]
verify: Waiting 1 seconds to verify that tasks are stable...

As you can see, a nice progress bar will display the status of the overall deployment.

Note: If you press Ctrl+C while the service is being created, it will be sent to background automatically

We'll check how update also works with the --detach paramter now.

docker service update -d=false --force --update-parallelism 0 top

Summary

Congratulations! You have completed the Swarm Synchronous Services lab. You can practice more labs in LabEx to improve your skills.