Hot and Cold Deployment in Tomcat

What is Hot Deployment?

These services can be added to or removed from the running server.it is the process to change in the currently deployed war file without re-deploying it. It is a time-saving process because the developer can simply run the build and have a new auto-deployed code instead of shutdown and startup is massive.

 
What is Cold Deployment?
Cold deployment is slow as compared with Hot deployment but it is stable. this is defined as a task that requires one or more instances of the server to restart to reflect the changes i.e. for every change, you need to restart the server then changes reflect.

Advantages and Disadvantages:

• Hot Deployment:-
  • Pros:
    1. The business will never be going to stop.
    2. It prevents you from the manual restart of production server if you made any changes to the contents of the war file being deployed.
  • Cons:
    1. Hot re-deployment of an application sometimes results in Out Of Memory errors.
    2. Hot deployment deploys simultaneously to all the nodes, resulting in downtime.
• Cold deployment:-
  • Pros:
    1. No caching + also no out of memory issues after subsequent deploys during testing.
  • Cons:
    1. Outage cost is more being a lengthy process.