Web Infrastructure
Apache Web Server
The leading open-source HTTP server for heterogeneous operating systems including. Provides a secure, efficient and extensible server that provides HTTP services.
http://www.apache.org
HA Proxy
HAProxy is a free, very fast and reliable solution offering high availability, load balancing, and proxying for TCP and HTTP-based applications
http://haproxy.1wt.eu/
Squid
Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages
http://www.squid-cache.org/
KeepAliveD
KeepaliveD is a strong & robust keepalive daemon facility providing heartbeat services.
http://www.keepalived.org/