LARTC - Apr 2007 - tc / MARK question

Hi,

I have a router, running iptables & tc, with 2 interfaces (eth0 & eth1).

I classify http traffic in iptables (prerouting mangle) coming in on eth0
and going out on eth1 with MARK 0x1, and I also classify return http traffic
coming from eth1 -> eth0 with MARK 0x1 as well. I then ACCEPT them in the
filter/FORWARD chain based on --mark 0x1.

However, I want to shape this traffic, and limit based on the 0x1 MARK. I
want to limit traffic to 4MBit outgoing on eth1 (incoming http), and 4MBit
outgoing on eth0 (return http), *independently*, even though they use the
same MARK.

If I use HTB, assigned to egress eth0 and another assigned to eth1, and
classify packets based on the MARK 0x1 (from above this is two tcp streams
in different connections under the same mark), does tc:

a) Treat the interfaces separately, giving me 4MBit either way independently
b) Treat the interfaces as one (because one MARK is being used), and give me
4MBit total across both streams?

Thanks!

Dan

Hi Dan,
>Hi,
>
>I have a router, running iptables & tc, with 2 interfaces
>(eth0 & eth1).
>
>I classify http traffic in iptables (prerouting mangle) coming in
>on eth0 and going out on eth1 with MARK 0x1, and I also classify
>return http traffic coming from eth1 -> eth0 with MARK 0x1 as well.
>I then ACCEPT them in the filter/FORWARD chain based on --mark 0x1.
>
>However, I want to shape this traffic, and limit based on the 0x1 MARK.
>I want to limit traffic to 4MBit outgoing on eth1 (incoming http), and
>4MBit outgoing on eth0 (return http), *independently*, even though they
>use the same MARK.
>
>If I use HTB, assigned to egress eth0 and another assigned to eth1, and
>classify packets based on the MARK 0x1 (from above this is two tcp
>streams in different connections under the same mark), does tc:
>
>a) Treat the interfaces separately, giving me 4MBit either way
>   independently
This is the correct answer.
Traffic Control is applied to each interface independently.
Didn''t you notice that when you configure a qdisc/class/filter
you must always specify the interface name ? :)
The fact that you use the same MARK in both directions has no
influence at all on the queueing.
>b) Treat the interfaces as one (because one MARK is being used), and
>   give me 4MBit total across both streams?
Regards
/Christian
[http://benve.info]