Dealing with Orphaned pod messages (Orphaned pod found - but volume paths are still present on disk)

clean_orphaned_pods.sh

#!/bin/bash -eu
#
# This script is designed to be run as a cron job periodically to
# clean up the Orphaned Pods. Use at your own risk!
#

## Settings (can be passed as environment variables)
LOGFILE=${LOGFILE:-/var/log/messages} # what log file to process
KUBELET_PODS_DIR=${KUBELET_DIR:-/var/lib/kubelet/pods} # where to find pods to remove
DEBUG=${DEBUG:-0} # more debug output


## Script Starts Here
last_pod=""

# Retrieve the most recent "Orphaned pod" log entry (tac =  backwards cat)
# NOTE: If there are no orphaned pods, then pod==last_pod, so its skips :)
while pod=$(tac ${LOGFILE} | grep -m 1 'Orphaned pod' | grep -o '".*"' | sed 's/"//g'); do
  if [[ $pod != $last_pod ]]; then
    last_pod=$pod
    pod_dir="${KUBELET_PODS_DIR}/${pod}"
    if [[ -d $pod_dir ]]; then
      # echo "$pod exist"
      rm -rf "${pod_dir}/volumes"
      if [[ $? == 0 ]]; then
        echo "Cleaned orphaned pod volumes: $pod"
      else
        echo "ERROR: Pod cannot be deleted: ${pod_dir}" >&2
      fi
    else
      [[ $DEBUG == 1 ]] && echo "DEBUG: $pod doesn't exist in directory (${pod_dir})"
    fi
  else
    [[ $DEBUG == 1 ]] && echo "DEBUG: No (more) orphaned pods found."
    break
  fi
  sleep 1
done

I would like to see if we can make the "find most recent Orphaned pod" more efficient:

while pod=$(tac ${LOGFILE} | grep -m 1 'Orphaned pod' | grep -o '".*"' | sed 's/"//g'); do

• tac = backwards cat (just found out about this, I usually scoff at people that use "cat file | grep" ;)
• Double grep :(
• sed to dequote

I feel like there is probably a better way to handle that... I am also not sure whether using tac LOGFILE | grep -m 1 'match' is more or less efficient than grep 'match' LOGFILE | tail -1