Cluster
Kubernetes Base Environment Requirements
· ☕ 4 min read
1. Base Packages Kubernetes version ≥ 1.18 socat Required conntrack Required ebtables Optional, but recommended ipset Optional, but recommended ipvsadm Optional, but recommended 1 apt-get -y install socat conntrack ebtables ipset ipvsadm 2. Port Requirements 2.1 Base Node Services Service Protocol Action Start Port End Port Comment ssh TCP allow 22 22 Node remote management docker TCP allow 2375 2376 Docker remote communication etcd TCP allow 2379 2380 etcd cluster communication 2.

How to Repair a Kubernetes Master Node After Reinstalling the OS
· ☕ 2 min read
Recently I ran into this twice: a host had to be reinstalled because of a failure. In one case only a single Etcd node was left, and the whole cluster stayed down for half an hour before it recovered. This post mainly records the process of initializing a fresh Ubuntu

Kubernetes Cluster Troubleshooting
· ☕ 6 min read
FailedCreatePodSandBox Error Error response from daemon: OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:402: getting the final child's pid from pipe caused: EOF: unknown Resolution Clear the cache 1 echo 3 > /proc/sys/vm/drop_caches Cause Too much memory fragmentation calico-node Keeps Restarting increase max user Error runtime: failed to

How to Repair a Kubernetes Cluster After Changing IPs
· ☕ 3 min read
A record of repairing a cluster failure caused by an IP change. There are two clusters: one single-node (allinone) cluster, and one four-node cluster (3 masters, 1 node). 1. Update the Etcd Certificates [On every Etcd node] Back up the Etcd certificates 1 cp -R /etc/ssl/etcd/ssl /etc/ssl/etcd/ssl-bak View the domains

Etcd and Etcdctl in Practice
· ☕ 5 min read
1. Basic Introduction to Etcd Etcd is a distributed Key/Value storage system. Through distributed locks, leader election, and write barriers it achieves distributed coordination, offering highly available, persistent data storage and retrieval services. How it works Every Etcd node stores a complete copy of the data, and at any moment