Re: [squid-users] Chaining proxies once more

For reference to the list I'm answering in english.. sorry.

On Thu, 28 Jun 2001, Andreas Tille wrote:

> Hello,
>
> once I´ve posted here a problem in chaining proxies. I have to try another
> question because my problem was not solved.

[...]

> cache_peer wittenau.ivbb.bund.de parent 80 3130 no-digest

[...]

> /var/log/squid/cache.log:
> 2001/06/28 08:37:48| Configuring Parent wittenau.ivbb.bund.de/80/3130
> 2001/06/28 08:38:57| temporary disabling (Bad Request) digest from wittenau.ivbb.bund.de
> 2001/06/28 08:39:38| Detected DEAD Parent: wittenau.ivbb.bund.de/80/3130

[...]

At first you must understand how squid works. It is not primarily a proxy,
but a cache, and AFAIK far beyond any other product you might come across
in that area.

In your case that means if a http request is received, it contacts the
other proxy, tries to learn if it can answer the request in a timely
manner (if it has cached that page already, for example) by ICP and what
else. Failing that (or not answered quickly enough) it will go get the
file itself.

This is not what *you* need here, but you can arrange for that to happen:

From the context I'd guess that the other proxy doesn't speak ICP etc. and
is just a dump proxy. According to the docs you should specify 7 as the
icp port (3130) and I'd suggest also the "no-query" and "default" options
in addition to no-digest which mean don't bother it with ICP queries, just
use it as the default proxy.

> The problem is, that squid doesn't get any usefull information from
> the proxy (don't know what squid-internal-dynamic/netdb is???). Instead
> it follows the default route and just fails at the firewall. So I

If you knew that already, why didn't you just use the options explained
in squid.conf?

> wonder, what options I have to change that squid never follows the
> default route to but instead only access the wittenau.ivbb.bund.de proxy.

Finally, to ensure that other proxy is always asked, even if it appears
dead slow or what else, use:

never_direct all

(AFAIK there used to be a default policy in squid which checked the site
 first for most actual info rather than asking yet another proxy).

I hope I didn't oversee anything. If this doesn't suffice, you definitely
should study all the comments in squid.conf and setup everything as you
need it.

> PS: I´m subscribed to this list but never get any answer to my E-mail
> address. ANy suggestion for this meta-problem so I do not have to
> browse the list archive???

Sorry, I can't. It works for me. Maybe your email address is broken?
(We'll see if my direct answer gets through).

Michael.

--
Michael Weller: eowmob@exp-math.uni-essen.de, eowmob@ms.exp-math.uni-essen.de,
or even mat42b@spi.power.uni-essen.de. If you encounter an eowmob account on
any machine in the net, it's very likely it's me.