On Sat, 29 Apr 2000, Andi Kleen wrote:
> On Sat, Apr 29, 2000 at 12:20:23AM +0200, Liang Han wrote:
> > 1. The routing should be resolved at IP level. My experience on
> > linux2.2.12 seems conflict with the principle. So what's the reason.
>
> Most likely the TOS setting in your redirects. The TOS in the Ip Header
> in the redirect has to match the TOS of the TCP connection. ftp and
> telnet both set TOS. Linux 2.2 has per TOS routing, so it uses
> TOS dependent routes. Checking TOS for redirects is arguably
> very pedantic, but it is like it is.
I have changed the TOS field of the redirect message. It works and
Telnet and Ftp sessiones go through the new route now. But I also need to
send another redirect message with Tos set to 0x0 to make Tracetoute
work.
My conclusion is under the scheme of per TOS routing, we can not totally
rely on traceroute, ping, route and ping programms to determine the
actual route.
Liang
|