RE: Problems with HAProxy, down servers and 503 errors

Willy,

> No problem, no time wasted yet !

Well, none of your time :) It took me far longer than it should have to realise my error. Regretable, packet captures are usually my first diagnostic tool. A mistake I won't make again any time soon.

> Have you at least found a solution to your issue ?

I've found a partial solution to my issue, and in fact, now I have a question that's relevant to the list. The backend server is IIS, if you're getting 503s during shutdowns, you can use this solution to turn them into RSTs [1].

The RST is sent by IIS after it receives the full client request from HAProxy (I suspect that it may want to see the Host header before it decides how it wants to treat the request). When HAProxy receives the RST it returns a 503 to the client (respecting the errorfile!). Despite the presence of "option redistribute", HAProxy does not send the request to another backend server.

If there was a way to get HAProxy to send the request to another functional real server at this time it would be great, though I fear that HAProxy no longer has the request information after having sent it to the server.

Any further advice would be much appreciated, I can provide packet captures off list if required.

-JohnF Received on 2009/01/26 01:06