I came accross this issue while testing Rancher in my dev Kubernetes Cluster. Trying to delete the cattle-system namespace caused the Namespace to get stuck on Terminating for +24 hours before I decided to investigate further.
Attempting to delete the namespace with –force –grace-period=0 had no affect.
After some time digging, I came across the below article which advised to edit the namespace to check for a “finalizer” field being set in the yaml config. Removing the below two lines and saved allowed the namespace to terminate immediately after closing the file.
spec: finalizers: - kubernetes