From collectd Wiki

There are three plugins collecting usage information from HAProxy, a free open-source load-balancing software for HTTP and TCP. The first two use the Exec plugin to run, the last one is a C Plugin.

• Plugin:haproxy.rb
• Plugin:haproxy-stat.sh
• https://github.com/Fotolia/collectd-mod-haproxy
• https://github.com/mleinart/collectd-haproxy

See also

• Exec plugin
• HAProxy homepage