Re: [squid-users] bypassing cache under certain circumstances

Hm, it doens't do this already?

Well, it certainly wouldn't be difficult to. File a bugzilla report;
see if it tickles the fancy of anyone.

Adrian

On Sat, Mar 08, 2008, Aurimas Mikalauskas wrote:
> Hello,
>
> For the setup I'm about to discuss, I used to use varnish, but due to
> stability issues decided to use squid instead. It's a rather usual
> reverse-proxy setup with squid 3.0. However, I do have one issue that
> could have been solved easily with varnish, but I can't find a good
> solution for squid. Thing is:
>
> Pages are cached. I want them to be cached, but.. there are some users
> that come with a Cookie NOCACHE. I want those users to get fresh
> pages, but at the same time, I want that other users would gather the
> cached pages as usually. I tried the following:
>
> acl nocache_cookie req_header Cookie NOCACHE
> cache deny nocache_cookie
>
> However, as described in
> http://www.squid-cache.org/Versions/v3/3.0/cfgman/cache.html - "use
> this to force certain objects to never be cached" and not only it does
> not cache then - but also updates it's cache lists that the object is
> not cached. So what I get is:
>
> #1 user comes w/o NOCACHE -- she gets a CACHE_MISS, page from
> originserver, and gets it cached
> #2 user comes w/o NOCACHE -- she gets a CACHE_HIT i.e. the cached page
> #3 user comes w/ NOCACHE -- she gets a CACHE_MISS and fresh page
> directly from originserver (page does not get cached)
> #4 user comes w/o NOCACHE -- she gets a CACHE_MISS, page from
> originserver, and gets it cached
>
> and obviously this is not what I want - I'd rather have page kept in
> cache at step #3 (at the same time feeding the page directly from
> originserver to user #3).
>
> In varnish I could have achieved that with
>
> sub vcl_recv {
> if (req.http.Cookie ~ "NOCACHE") {
> pass;
> }
> }
>
>
> Appreciate your thoughts!
>
> // Aurimas

-- 
- Xenion - http://www.xenion.com.au/ - VPS Hosting - Commercial Squid Support -
- $25/pm entry-level VPSes w/ capped bandwidth charges available in WA -