[j-nsp] Juniper CoS - Classifiers specifically

[aaron1 at gvtc.com]

Just looking to bounce this off anyone in the know.

 

As I learn more about Juniper CoS in Junos, it appears to me that a Juniper
device comes by default acting as a Behavior Aggregate classifier on each
interface that has an ip address enabled.  I'm saying this since I have IP's
on 3 interfaces, and I'm seeing Junos assign a default classifier to each of
those logical units.

 

I'm saying BA since I understand a BA classifier is one assigned using
class-of-service classifier like I see here. and not the other type MFC
(multi-field classifier) which uses a firewall filter

 

I'm wondering if the BA classifier stops working once an MFC is applied.  It
sure seems to in testing.  I feel like I've seen a diagram at some point or
document stating that MFC comes before BA in the CoS process chain. but I'm
not sure.  If anyone has that link/doc please send it.  I'd like to know for
sure.

 

Oh, btw, were in the world is all this default CoS stuff derived from?  I'd
like to think it's in a file somewhere that I can see in shell perhaps.  But
maybe not.  Maybe it's actually compiled into the Junos operating systems
itself.  Or is there a way to see "show configuration" with a special option
that shows automatic/default stuff like all this CoS info?

 

The available default classifiers.

 

root at srx-1> show class-of-service classifier | grep classifier

Classifier: dscp-default, Code point type: dscp, Index: 7

Classifier: dscp-ipv6-default, Code point type: dscp-ipv6, Index: 8

Classifier: dscp-ipv6-compatibility, Code point type: dscp-ipv6, Index: 9

Classifier: exp-default, Code point type: exp, Index: 10

Classifier: ieee8021p-default, Code point type: ieee-802.1, Index: 11

Classifier: ipprec-default, Code point type: inet-precedence, Index: 12

Classifier: ipprec-compatibility, Code point type: inet-precedence, Index:
13

Classifier: ieee8021ad-default, Code point type: ieee-802.1ad, Index: 41

 

 

The ipprec-compatibility classifier I find assigned to enabled interfaces.

 

root at srx-1> show class-of-service interface | grep
"object|classifier|logical"

  Logical interface: ge-0/0/0.0, Index: 74

Object                  Name                   Type                    Index

Classifier              ipprec-compatibility   ip                         13

 

  Logical interface: ge-0/0/1.0, Index: 75

Object                  Name                   Type                    Index

Classifier              ipprec-compatibility   ip                         13

 

  Logical interface: irb.0, Index: 73

Object                  Name                   Type                    Index

Classifier              ipprec-compatibility   ip                         13

 

 

Details of the classifier I see assigned to my enabled interfaces.

 

root at srx-1> show class-of-service classifier name ipprec-compatibility

Classifier: ipprec-compatibility, Code point type: inet-precedence, Index:
13

  Code point         Forwarding class                    Loss priority

  000                best-effort                         low

  001                best-effort                         high

  010                best-effort                         low

  011                best-effort                         high

  100                best-effort                         low

  101                best-effort                         high

  110                network-control                     low

  111                network-control                     high

 

 

(no user defined cos config is present)

root at srx-1> show configuration class-of-service | display set

 

root at srx-1>

 

 

 

 

Aaron

aaron1 at gvtc.com