[RFC] remove negative_ttl directive ?

The negative_ttl directive is continuously causing problems. What it
does is DoS all clients of a proxy when one of them has a URL problem.
In modern websites which can present per-client error responses targeted
at an individual client this can be a major problem.

I propose dropping the directive entirely and following HTTP RFC
guidelines about cacheability of 4xx-5xx responses.

The one case I can think of it actually being useful is to prevent DDoS
against a reverse-proxy. However, due to DDoS usually varying the URL
anyway this is an extremely weak protection.

Can anyone present any actually useful reason to keep it despite the
problems it presents?

Amos
Received on Fri Jan 11 2013 - 05:53:27 MST