I am setting up a reverse-proxy system with Nginx (0.8.32) both as
back-end and proxy. The system is used for delivering static large
What I would like to achieve is caching the files on the proxies as long
as possible offloading the back-end. I would also like the proxy to
react to changes on the back-end, but without retransmitting already
cached unmodified content.
My problem is that I’m not able to get the proxy to revalidate
unmodified static content without retransmitting the already cached
file. E.g. if I set proxy_cache_valid for 200/OK delivered content to 60
minutes the proxy won’t react to changes in the back-end for that period
of time, and if I set it to 1 minute the file will be retransmitted from
back-end to proxy every minute, if requested from the proxy by a client.
What I would like is, for example, for the proxy to revalidate cached
content with I-M-S set to the time of the content being cached and if
not modified refreshing the validity of the previously cached content
and returning it to the client.
I’ve looked through the documentation and played with cache-control
directives like for example pre/post-check without succeeding in
creating this behaviour. There probably is an obvious answer to this
question, only I haven’t been able to find it.