Switching

We got a provider of IPTV connected to gigabit port of J4200 connected as access vlan and transited pass to MSDP enabled router

I need to remark all dscp field in the traffic wich passed from this port 

how to i can do this?

Hi,

You may apply a firewall filter that matches all traffic and sets the forwarding class:

family ethernet-switching {

    filter video {

        term 1 {

            then {

                forwarding-class expedited-forwarding;

                loss-priority low;

            }

        }

    }

}

set interfaces ge-x/y/z unit 0 family ethernet-switching filter input video

thats not work =(

thats is placed all trafic in the expedited-forwardig class

but not rewrite dscp 

and i need to rewrite all incoming dscp to dscp 46 in this port

You can apply the default rewrite rule to the interface toward router:

set class-of-service interfaces ge-x/y/z unit 0 rewrite-rules dscp default

Be careful on rewrite rules.. As JUNOS rewrites DSCP/COS on egress  (vs ingress on the interface you want) you might accidentally overwrite other traffic that you had marked intentionally already.

a can JunOS remark DSCP/COS on specific vlan?

in the documentation i found 

}

[edit]
root# show class-of-service 
forwarding-classes {
    class voice queue-num 5;
}
rewrite-rules {
     ieee-802.1 voice {
         forwarding-class voice {
             loss-priority low code-point 110;
         }
     }
}
root# show firewall 
family ethernet-switching {
     filter rewrite-filter {
         term voice {
             from {
                 dscp ef; # any condition could be specified here
             }
             then {
                 forwarding-class voice;
                 loss-priority low;
                 count voice-hits;
             }
         }
     }
}
root# show interfaces ge-0/0/0 
unit 0 {
    family ethernet-switching {
        port-mode trunk;
        vlan {
            members 1;
        }
        filter {
            output rewrite-filter;
        }
    }

but when i'ь trying to apply filter on a specific vlan on output 

ex4200 not commited config

---

@cmhungry wrote:

a can JunOS remark DSCP/COS on specific vlan?

in the documentation i found 

root# show firewall 
family ethernet-switching {
     filter rewrite-filter {
         term voice {
             from {
                 dscp ef; # any condition could be specified here
             }
             then {
                 forwarding-class voice;
                 loss-priority low;
                 count voice-hits;
             }
         }
     }
}
root# show interfaces ge-0/0/0 
unit 0 {
    family ethernet-switching {
        port-mode trunk;
        vlan {
            members 1;
        }
        filter {
            output rewrite-filter;
        }
    }

but when i'ь trying to apply filter on a specific vlan on output 

ex4200 not commited config

---

Although you are applying your filter on outbound, it is really just reclassifying the traffic.  Firewall filters themselves don't do any rewrite operations.

Typical approaches utilize a firewall filter on inbound for classifying the traffic (called a Multifield Classifier) and then utilizing a rewrite-rule on the outbound interface to rewrite the DSCP bits based on the associated forwarding-class of the traffic (which was associated through the use of the MF classifier).

thanks 😃

thats working!!!

this is nor worked too =(