[j-nsp] juniper-nsp Digest, Vol 148, Issue 34

[Amarjeet Singh]

Hello Cydon - First thing that strike my mind is missing EXP classifier
under routing-instance.
If it's not there apply and test it out.

Br, Amarjeet


>
>
>
> Message: 1
> Date: Sat, 28 Mar 2015 14:37:43 +0100
> From: Cydon Satyr <cydonsatyr at gmail.com>
> To: juniper-nsp at puck.nether.net
> Subject: [j-nsp] Rewriting customer DSCP with MPLS EXP
> Message-ID:
>         <CAF0PUwe+02yJgs9DGpenvHNngYXtK60=
> kXKWiVWFS7zWs7LfRg at mail.gmail.com>
> Content-Type: text/plain; charset=UTF-8
>
> I stumbled upon something I can't get my head around.
>
> I've been doing some CoS testing; it's a simple L3VPN network, and at the
> egress PE router,
> I want to rewrite customer dscp with whatever exp value I classified from
> core interface.
>
> The topology is actually two M320 connected back to back with 4 logical
> system.
>
>
>
>
> [C1]---ge-2/0/0-----[PE1]---------------[P1]-----------------[P2]-------------[PE2]----ge-2/0/0----[C2]
>
>
>
> PE1 and P2 are first router M320, and P1 and PE2 are second M320 router.
> C-routers are separate routers.
>
> Core links are all ge-2/1/0 with .1q tags.
>
>
> This is config on both routers (logical system's QoS are also in master
> instance):
>
> [edit class-of-service interfaces]
> ge-2/0/0 {
>     unit * {
>         forwarding-class REALTIME;
>         rewrite-rules {
>             dscp RW-dscp;
>         }
>     }
> }
> ge-2/1/0 {
>     unit * {
>         scheduler-map SCM;
>         classifiers {
>             dscp BA-dscp;
>             exp BA-exp;
>         }
>         rewrite-rules {
>             dscp RW-dscp;
>             exp RW-exp;
>         }
>     }
> }
>
> my exp classifier:
>
> forwarding-class BE {
>     loss-priority low code-points 000;
>     loss-priority high code-points 001;
> }
> forwarding-class REALTIME {
>     loss-priority high code-points 101;
> }
> forwarding-class VIDEO {
>     loss-priority low code-points 010;
>     loss-priority high code-points 100;
> }
> forwarding-class CRITICAL {
>     loss-priority low code-points 111;
>     loss-priority high code-points [ 110 011 ];
> }
>
>
> The customer traffic gets classified in REALTIME with PLP low. The exp
> rewrite rule marks outgoing packet with
> 101.
>
> The issue is this, on all routers I see traffic classified and marked with
> 101. On the egress PE router, however,
> I see traffic classified as VIDEO (which require exp marking of 010 or
> 100). At the same time the customer receives
> traffic marked with 100. It is if for some reason the last router
> classified traffic with VIDEO and marked outgoing
> dscp with VIDEO.
>
> I can't seem to understand why this is happening. The thing I see is
> default exp classification is this:
>
>
> run show class-of-service classifier type exp name exp-default
> Classifier: exp-default, Code point type: exp, Index: 10
>   Code point         Forwarding class                    Loss priority
>   000                BE                                  low
>   001                BE                                  high
>   010                REALTIME                            low
>   011                REALTIME                            high
>   100                VIDEO                               low
>   101                VIDEO                               high
>   110                CRITICAL                            low
>   111                CRITICAL                            high
>
>
> In default exp classifier, marking of 101 goes to VIDEO, not REALTIME.
> But as you can see I have the correct configuration on all interfaces...or
> do I?
>
> Why are all routers classifying traffic correctly as REALTIME and marking
> 101, when the egress PE is
> classifying as VIDEO ? The same thing happens in other direction.
>
>
> I spend couple of days on this and can't seem to figure it out.
>
>
> Thanks!
>
>
>
> ********************************************
>