what workloads we gonna run on k8s cluster web analytics CPU intensive memory intensive heavy traffic etc... Choosing k8s infrastructure Configure high availability ETCD in HA minikube kubeadm
1. have to use multiple masters Master node hosts the control plane components Multiple masters in Active-Active mode. And configure the Loadbalancer to route traffic to both the masters master1: https://master1:6443 -- Active master2: https://master2:6443 -- Active LB --> https://load-balancer:6443 but Active-Active some issues in scheduling pods if we go Active-Standby mode we need to use leader-elect which controller manager is leader kube-controller-manager \ --leader-elect true [other options] \ --leader-elect-lease-duration 15s \ --leader-elect-renew-deadline 10s \ --leader-elect-retry-period 2s master1: https://master1:6443 -- Active master2: https://master2:6443 -- Standby
ETCD --> RAFT Protocol etcd --> distributed!!! etcd cluster --> 3 etcd nodes for high availability. Quorum = N/2 + 2 etcd leader elect using RAFT algorithm. in etcd cluster --> minimum 3 nodes is madatory because of Quorum. ETCDCTL_API=3 ETCD odd nodes are preferrable.