From e4ff8eb6df90e5badc4dde978efe69e99b0020a5 Mon Sep 17 00:00:00 2001
From: Sheogorath <sheogorath@shivering-isles.com>
Date: Sat, 15 Jan 2022 02:25:20 +0100
Subject: [PATCH] fix(kube-system): Repair quorum idea for masters
This patch fixes the usage of the PodDisruptionBudget (PDB) in order to
achieve a quorum functionality for the master nodes by deploying a pause
container on all of them. Main reason to do that, is the inability of a
PDB to operate on static-pods or daemonsets. Therefore this deployment
will make sure, that only one master node will become unavailable at the
time.
---
.../kube-system/poddisruptionbudget.yaml | 4 +-
infrastructure/kube-system/quorum.yaml | 43 +++++++++++++++++++
2 files changed, 45 insertions(+), 2 deletions(-)
create mode 100644 infrastructure/kube-system/quorum.yaml
diff --git a/infrastructure/kube-system/poddisruptionbudget.yaml b/infrastructure/kube-system/poddisruptionbudget.yaml
index d394efaa2..cfe2b4b1e 100644
--- a/infrastructure/kube-system/poddisruptionbudget.yaml
+++ b/infrastructure/kube-system/poddisruptionbudget.yaml
@@ -12,12 +12,12 @@ spec:
apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
- name: etcd
+ name: quorum
namespace: kube-system
spec:
maxUnavailable: 1
selector:
matchLabels:
- component: etcd
+ component: quorum
tier: control-plane
diff --git a/infrastructure/kube-system/quorum.yaml b/infrastructure/kube-system/quorum.yaml
new file mode 100644
index 000000000..4b95c6e12
--- /dev/null
+++ b/infrastructure/kube-system/quorum.yaml
@@ -0,0 +1,43 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+ name: quorum
+ namespace: kube-system
+ labels:
+ component: quorum
+ tier: control-plane
+spec:
+ replicas: 3
+ selector:
+ matchLabels:
+ component: quorum
+ tier: control-plane
+ template:
+ metadata:
+ labels:
+ component: quorum
+ tier: control-plane
+ spec:
+ affinity:
+ nodeAffinity:
+ requiredDuringSchedulingIgnoredDuringExecution:
+ nodeSelectorTerms:
+ - matchExpressions:
+ - key: node-role.kubernetes.io/control-plane
+ operator: Exists
+ podAntiAffinity:
+ requiredDuringSchedulingIgnoredDuringExecution:
+ - labelSelector:
+ matchExpressions:
+ - key: component
+ operator: In
+ values:
+ - quorum
+ topologyKey: kubernetes.io/hostname
+ tolerations:
+ - key: node-role.kubernetes.io/master
+ operator: Exists
+ effect: NoSchedule
+ containers:
+ - name: pause
+ image: k8s.gcr.io/pause
--
GitLab