[j-nsp] Juniper MX5 not forwarding dscp information.

[Gustavo Santos]

We're just added a http/p2p caching appliance in our network. One of this
appliance feature is to tag/mark with a dscp number the cache_hit packet
and with that dscp information, we can set our BRAS to provide more
bandwidth to our customers from traffic generated by the Cache engine.

After doing some tests , our BRAS and even a laptop with wireshark directly
connected to the Juniper router gets the packets from cache with no dscp
code set.

To make sure that the problem isn't with the cache engine, I did a firewall
filter below and applyed to the interface connected to the cache.

term 10 {
    from {
        dscp af12;
    }
    then {
        count cache_out;
        accept;
          }
}
term 20 {
    then accept;
}

And the counter worked as suposed. Counting the dscp hit packets as it
should.

But, the information isn't forwarded to another interfaces. Even testing a
ping packet with TOS value set from the routing engine Lo0 interface to my
laptop or the BRAS, the packets forwarded come without the dscp tag set.

The Junos version os 12.1R9.





Gustavo Santos
Analista de Redes
CCNA , MTCNA , MTCRE, MTCINE, JUNCIA-ER