upstream content checks

[Michael Shadle]

On Fri, Apr 24, 2009 at 8:26 AM, Smatchimo <nginx-forum at nginx.us> wrote:
> 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!

I've asked for this for a bit... :)

Right now the only answer is to use an external monitoring program
such as ldirectord or a home-made thing to check, have your upstreams
stored in an include file, and add/remove them as needed and send
nginx an appropriate HUP signal to reload it when things change.