[j-nsp] (Again) Rewriting IP precedence

[Sorin CONSTANTINESCU]

Hi,

It's not the first time i run into this problem, but i hope this time
i'll be able to explain the problem better to you and get some help :)

- R1 -
Hardware: Juniper M5
Software:  7.3R1.6

I have the following topology:

_Host_A_ ---> R1 -> R2 -> R3 -> R4 ---> _Host_B_
                                |
                          _Host_C_

The network is configured to run MPLS.

On the ingress interface (dot1q gigabit subinterface), i have a
firewall filter that changes the default forwarding-class
(best-effort) to assured-forwarding with plp low.

Under [class-of-service], i've defined a rewrite rule for inet-precedence:

=== cut here ===
rewrite-rules {
    inet-precedence clear-inet-precedence {
        forwarding-class assured-forwarding {
            loss-priority low code-point 000;
        }
    }
}
=== and here ===

If i ping Host C from Host A, the precedence is correctly rewriten to
000. If i ping Host B from Host A, the precedence is not cleared.

The difference is that traffic from A to B is label-switched, and from
A to C is not.

I've also configured a rewrite-rule to clear exp precedence , but the
precedence of the IPV4 packet inside is not cleared to 0x00.

Thanks,
--
Sorin CONSTANTINESCU
JNCIS-M, CCNP
consta at gmail.com