This script assign static IP to all nodes of a kind cluster

kind_static_ips.sh

#!/bin/bash
set -e

# Workaround for https://github.com/kubernetes-sigs/kind/issues/2045
all_nodes=$(kind get nodes --name "${CLUSTER_NAME}" | tr "\n" " ")
declare -A nodes_table
ip_template="{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}"

echo "Saving original IPs from nodes"

for node in ${all_nodes}; do
  nodes_table["${node}"]=$(docker inspect -f "${ip_template}" "${node}")
  echo "${node}: ${nodes_table["${node}"]}"
done

echo "Stopping all nodes and registry"
docker stop ${all_nodes} "${reg_name}" >/dev/null

echo "Re-creating network with user defined subnet"
subnet=$(docker network inspect -f "{{(index .IPAM.Config 0).Subnet}}" "kind")
echo "Subnet: ${subnet}"
gateway=$(docker network inspect -f "{{(index .IPAM.Config 0).Gateway}}" "kind")
echo "Gateway: ${gateway}"
docker network rm "kind" >/dev/null
docker network create --driver bridge --subnet ${subnet} --gateway ${gateway} "kind" >/dev/null

echo "Assigning static IPs to nodes"
for node in "${!nodes_table[@]}"; do
  docker network connect --ip ${nodes_table["${node}"]} "kind" "${node}"
  echo "Assigning IP ${nodes_table["${node}"]} to node ${node}"
done

echo "Starting all nodes and registry"
docker start ${all_nodes} "${reg_name}" >/dev/null

echo -n "Wait until all nodes are ready "

while :; do
  [[ $(kubectl get nodes | grep Ready | wc -l) -eq ${#nodes_table[@]} ]] && break
  echo -n "."
  sleep 5
done

echo

hello,

It does not work because when kind launch the cluster it created an endpoint for the API server with the old IP in default namespace
After this when you change the IP with your script, the endpoints stay with the old IP and the API server is down

regards,

Yes, you are right.