Re: ip_wccp.c for WCCP v2 question

Ok...Way over /my/ head, as I'm only the messenger trying to help Kevin
debug the problems he's run into. But I'll do some studying. I've just
built a new kernel RPM with the patch that includes the module closing
code that Henrik spotted as MIA. Will see if that fixes our oops
problems. I'm awaiting Kevin getting back to the site where the cache
is (it's a remote site...so an oops is painful!). We'll probably get
the new kernel running tomorrow.

Since we're still using 2.2 series kernels I'm not yet looking into
netfilter, but I will do that soon, as WCCP v2 support is too good to
let fall by the wayside. Have any/all of the other tunneling modules
been updated to work with netfilter so I can learn from them?

Big thanks to Roger and Henrik, for the excellent pointers. I'll wrap
my head around these things as quickly as possible. And I'll probably
create a CVS branch for WCCP once we've got things running at Kevin's
site.

As I mentioned, v1/v2 in the same Squid needs some fixing--I'm going to
have to study the protocol some more, and the wccp.c code to see if they
can both fit in the same file and configuration option, or if they ought
to be separated out into a wccp2_router option and wccp2.c file
(thoughts, anyone? v2 allows multiple routers and the cache can tell
the routers more information about itself--so more configuration options
are needed for complete v2 support).

Henrik Nordstrom wrote:

> Roger Venning wrote:
>
>> Looking at net/ipv4/ipip.c as a guide, what Joe has done looks
>> reasonable. Can you send
>> me a dump of an oops (using the ksymoops tool) Joe?
>
>
> I got myself a copy of the kernel sources (only had the headers), and
> the "old" way indeed seems to be the correct one, used both by ipip and
> ip_gre.
>
> I am still a bit questioning about the validity of the mac magic (don't
> think many things expects the mac layer to be IP...) but it is shared
> with these modules as well.
>
> The packet size concerns still is there, and the same concerns apply to
> ipip and ip_gre. Both are quite sloppy with packet size checks.
>
> One thing which is missing from ip_wccp is 2.4 netfilter integration.
> See ip_gre.c. Should not be a big problem, but might cause some
> confusion if used together with netfilter conntrack...
>
> A further "cosmetic" thing is to send ICMP PROTOCOL UNREACHABLE on
> non-WCCP packets..
>
> /Henrik

                                   --
                      Joe Cooper <joe@swelltech.com>
                  Affordable Web Caching Proxy Appliances
                         http://www.swelltech.com
Received on Sat Mar 17 2001 - 21:16:07 MST