Haproxy Server Load balancer and redis Cache Server

The Q & A community network stackexchange consists of more than 100 websites, including stackoverflow, which is ranked 54th by Alexa. Stackexchang has 4 million users, with 0.56 billion PV per month, but only 25 servers are used, and the CPU load is not high.

It does not use cloud computing, because cloud computing may slow down, making it more difficult to optimize and eliminate system faults.

Stackoverflow still uses Microsoft's architecture. It is very practical. Microsoft's infrastructure can work effectively and is cheap enough. There is no convincing reason to make changes. But this does not mean that it does not use Linux. It uses Linux in a meaningful place.

Its Windows server runs Windows 2012 R2 and centos 6.4 on Linux server.

Website database ms SQL Size 2 TB, all stored on SSD, it has 11 web servers running IIS, 2 load balancing servers running haproxy, two cache servers running redis.