Why are AWS Batch Jobs stuck in RUNNABLE?

Question

I use a computing environment of 0-256 m3.medium on demand instances. My Job definition requires 1 CPU and 3 GB of Ram, which m3.medium has.

What are possible reasons wh

Answer 1

I just fought with this for a while, and found the answer.

One possible reason jobs can get stuck in Runnable is because there are no instances to run the job on. If this is the case, looking at the auto scaling group as mentioned in the above answer can show you the actual error that's preventing instances from being started, guiding you to the exact problem rather than leaving you to try any number solutions to problems you don't have. Error messages are our friends.