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Calrifications sought on processing of COS

‎10-21-2019 03:11 AM

Hi,

I am confused on COS processing. I have attached configuration as well. Apologies for  multiple attachments.

 

Description

1. Interface xe-0/0/2 is connected to ISP. The same port is in vlan 1701.

  

show configuration interfaces xe-0/0/2 

traps;
ether-options {
    no-flow-control;
}
unit 0 {
    family ethernet-switching {
        port-mode access;
        vlan {
            members 1701;
        }
    }
}

Vlan1701 {
    
    vlan-id 1701;
    filter {
        input pm_sig_classes_internet;
    }
    l3-interface vlan.1701;
}

2. There is rewrite rule for the same interface , file attached.

  

show class-of-service interface xe-0/0/2 
Physical interface: xe-0/0/2, Index: 132
Queues supported: 8, Queues in use: 8
  Scheduler map: scheduler_to_forwarding_class_map, Index: 27516
  Congestion-notification: Disabled

  Logical interface: xe-0/0/2.0, Index: 74
Object                  Name                   Type                    Index
Rewrite                 forwarding_class_to_dscp_map dscp              50147
Classifier              ieee8021p-untrust      untrust                    16

3. vlan 1701 also has input policy called pm_att_classes_internet which is defined below

    

 show configuration firewall family ethernet-switching filter pm_att_classes_internet 
apply-groups [ cm_trusted_links cm_sig_class4_exception cm_sig_class2_protocol cm_sig_class2v_ipaddr cm_sig_class3_protocol cm_class-default ];

4. Those groups detail is provided as an attachment.

 

Question:

1. There is input policy for vlan1701 and also rewrite rule for interface xe-0/0/2  ( belongs to vlan 1701 ) . So, will re write occur before input policy is processed ?

2. Rewrite rule on interface xe-0/0/2, is it inbound or outbound ?

2 REPLIES 2
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Re: Calrifications sought on processing of COS

‎10-21-2019 03:22 AM
 

Attachments

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Re: Calrifications sought on processing of COS

‎10-21-2019 04:59 AM

Hi,

 

Short answers to the questions:

1. Policing is done before remarking.

2. Remarking is on outbound/egress traffic.

 

Ref: https://www.juniper.net/assets/us/en/local/pdf/books/day-one-poster-junos-cos.pdf

 

Cheers,

Ashvin

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