Category: Cluster-HA

Installing Rancher 2 HA Cluster with Let’s Encrypt

All you need to create HA cluster with Rancher 2 on Debian/Ubuntu or anything else (I’m using Debian 9 as an example). You’ll need basic understanding of Kubernetes.

Rancher is Open Source enterprise cluster management software, more information on

Installing Rancher now as easy as possible, there’s official manual how to do that. It’s very detailed, except how to actually use Let’s Encrypt certificates. Continue reading


Install and configure a multi-master Kubernetes cluster with kubeadm

Kubeadm is a tool which is part of the Kubernetes project. It is designed to help with the deployment of Kubernetes. It is currently a work in progress and it has some limitations. One of these limitations is that it doesn’t support multi-master (high availability) configuration. This tutorial will go through the steps allowing to work around this limitation.

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Use HAProxy to load balance 300k concurrent tcp socket connections: Port Exhaustion, Keep-alive and others

I’m trying to build up a push system recently. To increase the scalability of the system, the best practice is to make each connection as stateless as possible. Therefore when bottleneck appears, the capacity of the whole system can be easily expanded by adding more machines. Speaking of load balancing and reverse proxying, Nginx is probably the most famous and acknowledged one. However, TCP proxying is a rather recent thing. Continue reading

MySQL 5.7 Multi-Source Replication – Automatically Combining Data From Multiple Databases Into One

MySQL’s multi-source replication allows you to replicate data from multiple databases into one database in parallel (at the same time). This post will explain and show you how to set up multi-source replication. (WARNING: This is a very long and detailed post. You might want to grab a sandwich and a drink. Continue reading