Re: Transparent Proxy/Cisco Shiva/Telebit/Tribelink

Marc Lucke wrote:

> Today I decided to use our cisco for transparent proxy. None of our
> dial-in customers on our Shiva access switch experience any problems
> but all of our users on the Telebit ISDN router & the tribelink cannot
> access web pages unless the specify our proxy server - yet they can
> get to any web page on our local network. I have tried a lot of
> things - it all seems very, very default to me but still will not
> work!

Hard to tell without doing packet traces of what is going on.

Perhaps it is path MTU discovery? Path MTU discovery will not work from
the proxy to the client when running a transparent proxy.

Try setting the MTU of the client interface on the proxy to some small
value like 526 or disable path MTU discovery by running "echo 1
>/proc/sys/net/ip_no_pmtu_disc".

--
Henrik Nordstrom
Squid hacker