PVC annotation fix

pvc-annotation-fix.sh

#!/usr/bin/env bash

# Requirements:
# 1. kubectl
# 2. jq

# While updating - or replacing - nodes, PVC annotation are kept for dead node.
# This makes it that some pods can't initialize because kubernetes
# can't attach a volume to it.

# This script clean the selected-node annotation from all PVC where the node
# doesn't exist, allowing for them be attached to new nodes.
declare -A nodes
while read node; do
  nodes["${node#node/}"]=exists
done < <(kubectl get nodes -o name)

kubectl get pvc -A -o json |
jq '.items[].metadata | [.namespace, .name, .annotations["volume.kubernetes.io/selected-node"]] | @tsv' -r |
while read namespace name node; do
  test -n "$node" || continue
  if ! [[ ${nodes[$node]-} == "exists" ]]; then
    kubectl annotate -n "${namespace}" "pvc/${name}" volume.kubernetes.io/selected-node-
  fi
done