I'm testing out the free trial to evaluate the APM features. My apps are Java apps running in docker containers on AWS ECS. I have set up an jvm app agent in each container to start up with the app when they are created. Deployments replace the all containers with zero downtime deployments, and i am using a 'chaos monkey' like system to randomly kill containers to test there is no downtime.
I have noticed with app agent that when a new app agent start, the old one is not deleted, which leaves the node count higher than it is, and also uses up licenses. I haven't been able to work out from the documentation if this is the behaviour I should be expecting to happen, or if there is some set up I have not found to make sure the agents are deregistered when the containers are stopped/killed?
Any help on this would be really useful.
Hi J.B. thank you for your response and the useful links.
From the notes on licensing I was interested by this statement:
For licensing purposes, the Controller releases the license for the agent if the Controller has not received data from the agent in the previous 5 minutes. This license availability behavior is not affected by the historical node status or node deletion timeout settings.
This sounds like there is a hard limit on when licenses are released. Would it therefore be the case that if I had a cluster of 3 apps in containers, and wanted to do a blue/green deployments such that I brought up 3 new instances of the app, and then took down the old 3 when the new are stable, that I would need to have 6 licences?