Add contrib script to rotate control plane to new nodes

contrib/migrate_control_plane/migrate_control_plane.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+ansible-inventory "$@" --list > /tmp/base_inventory.json
+
+NUMBER_OF_CONTROL_PLANE=$(jq < /tmp/base_inventory.json '[(.kube_control_plane.hosts | length), (.etcd.hosts | length)] | max')
+
+export BASE_INVENTORY_FILE=/tmp/base_inventory.json
+export ANSIBLE_INVENTORY=$(dirname $0)/rotate_inventory.py
+
+# TODO: remove this when switching to collection only
+KUBESPRAY_ROOT=${KUBESPRAY_ROOT:-$(dirname $0)/../..}
+export ANSIBLE_ROLES_PATH=$KUBESPRAY_ROOT/roles
+export ANSIBLE_LIBRARY=$KUBESPRAY_ROOT/library
+
+# Delete last control plane
+INDEX=0 ansible-playbook $ANSIBLE_PLAYBOOKS_ARGS $KUBESPRAY_ROOT/playbooks/remove_node.yml -e node='{{ [groups.kube_control_plane[-1], groups.etcd[-1] ] | reject("in", groups.new_etcd + groups.new_kube_control_plane) }}'
+# Add new control plane (last place), will be switched to first place in the first loop iteration
+ROTATION=1 INDEX=1 ansible-playbook $ANSIBLE_PLAYBOOKS_ARGS $KUBESPRAY_ROOT/playbooks/upgrade_cluster.yml
+for ((index=1;index<NUMBER_OF_CONTROL_PLANE;index++))
+do
+    # add new control plane / reorder
+    INDEX=$index ansible-playbook $ANSIBLE_PLAYBOOKS_ARGS $KUBESPRAY_ROOT/playbooks/upgrade_cluster.yml
+    # Update localhost loadbalancer control-plane on nodes
+    ansible-playbook $ANSIBLE_PLAYBOOKS_ARGS $KUBESPRAY_ROOT/playbooks/upgrade_cluster.yml --tags nginx,haproxy -l kube_cluster
+    # remove old control plane
+    INDEX=$index ansible-playbook $ANSIBLE_PLAYBOOKS_ARGS $KUBESPRAY_ROOT/playbooks/remove_node.yml -e node='{{ [groups.kube_control_plane[-1], groups.etcd[-1] ] | reject("in", groups.new_etcd + groups.new_kube_control_plane) }}'
+
+done
+
+# Last iteration is done separately because we don't need a remove-node step.
+INDEX=$index ansible-playbook $ANSIBLE_PLAYBOOKS_ARGS $KUBESPRAY_ROOT/playbooks/upgrade_cluster.yml

contrib/migrate_control_plane/rotate_inventory.py

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+#!/usr/bin/env python
+
+import json
+import os
+import sys
+
+with open(os.getenv("BASE_INVENTORY_FILE"), "r") as inventory_file:
+    inventory = json.load(inventory_file)
+index = int(os.getenv("INDEX"))
+rotation = int(os.getenv("ROTATION", "0"))
+kube_cp = (
+    inventory["new_kube_control_plane"]["hosts"][:index]
+    + inventory["kube_control_plane"]["hosts"][
+        slice(None, None if index == 0 else -index)
+    ]
+)
+kube_cp = kube_cp[rotation:] + kube_cp[:rotation]
+inventory["kube_control_plane"]["hosts"] = kube_cp
+etcd_cp = (
+    inventory["new_etcd"]["hosts"][:index]
+    + inventory["etcd"]["hosts"][slice(None, None if index == 0 else -index)]
+)
+etcd_cp = etcd_cp[rotation:] + etcd_cp[:rotation]
+inventory["etcd"]["hosts"] = etcd_cp
+json.dump(inventory, fp=sys.stdout)