rkt has a built-in garbage collection command that is designed to be run periodically from a timer or cron job.
Stopped pods are moved to the garbage and cleaned up during a subsequent garbage collection pass.
gc pass removes any pods remaining in the garbage past the grace period.
Read more about the pod lifecycle.
# rkt gc --grace-period=30m0s Moving pod "21b1cb32-c156-4d26-82ae-eda1ab60f595" to garbage Moving pod "5dd42e9c-7413-49a9-9113-c2a8327d08ab" to garbage Moving pod "f07a4070-79a9-4db0-ae65-a090c9c393a3" to garbage
On the next pass, the pods are removed:
# rkt gc --grace-period=30m0s Garbage collecting pod "21b1cb32-c156-4d26-82ae-eda1ab60f595" Garbage collecting pod "5dd42e9c-7413-49a9-9113-c2a8327d08ab" Garbage collecting pod "f07a4070-79a9-4db0-ae65-a090c9c393a3"