[JENKINS-71445] Reuse stopped EC2 instance,speed up maven build

This plugin is a great plugin. But after using it down to find a problem: 

I could not re-enable the stopped EC2 agent, but had to create a new instance.

As for why I need to re-use a stopped EC2 agent, it's because my maven project will download a lot of packages when I build it, and I don't want to repeat the download every time, which will increase my build time.  

If it could reuse the previous instance, then it wouldn't have to re-download these dependencies

---
Originally reported by alliot, imported from: Reuse stopped EC2 instance,speed up maven build

• assignee: thoulen
  
• status: Open
  
• priority: Major
  
• component(s): ec2-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 2
  
• imported: 2025-12-06
  

This plugin is a great plugin. But after using it down to find a problem: 

I could not re-enable the stopped EC2 agent, but had to create a new instance.

As for why I need to re-use a stopped EC2 agent, it's because my maven project will download a lot of packages when I build it, and I don't want to repeat the download every time, which will increase my build time.  


If it could reuse the previous instance, then it wouldn't have to re-download these dependencies

Start by tracing the ec2-plugin behavior for stopped EC2 agents and how it falls back to creating a new instance. Clarify the expected reuse lifecycle, then define tests showing that a stopped agent can be restarted and its Maven dependencies remain available.

Written by the indexing model from the issue text.