Does anyone know of any addons to nginx that would let it do content checks to
determine if an upstream server is alive or not, i.e. check a certain page for a
given string?

We are hoping to replace a lot of old ldirectord load balancers but this is a
feature we really need to have. All too often a web server (cough cough IIS)
will be responding to connections but giving errors instead of showing valid
content (cough cough ASP.NET), but by doing a content check the load balancer
will take the broken server out of the farm.

Thanks!

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,1422,1422#msg-1422