Using an ip acl to mark dscp values (dscp marking), Combined acl for 802.1p marking, Using an ip acl to mark dscp values – Brocade FastIron Ethernet Switch Security Configuration Guide User Manual

Page 137: Dscp marking)

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The dscp-cos-mapping option maps the DSCP value in incoming packets to a hardware table that
provides mapping of each of the 0 - 63 DSCP values, and distributes them among eight traffic classes
(internal priorities) and eight 802.1p priorities.

NOTE
The dscp-cos-mapping option overrides port-based priority settings.

By default, the Brocade device does the 802.1p to CoS mapping. If you want to change the priority
mapping to DSCP to CoS mapping, you must enter the following ACL statement.

permit ip any any dscp-cos-mapping

The complete CLI syntax for this feature is shown in

Extended numbered ACL configuration

on page

112 and

Extended named ACL configuration

on page 118. The following shows the syntax specific to

the DSCP Cos mapping feature.

[ dscp-marking dscp-value dscp-cos-mapping ]

or

[ dscp-cos-mapping ]

NOTE
The dscp-cos-mapping option should not be used when assigning an 802.1p priority. To assign an
802.1p priority to a specific DSCP (using dscp-match ), re-assign the DSCP value as well. For
exampledevice(config)#access-list 100 permit ip any any dscp-match dscp-marking
802.1p internal

Using an IP ACL to mark DSCP values (DSCP marking)

The dscp-marking option for extended ACLs allows you to configure an ACL that marks matching
packets with a specified DSCP value. You also can use DSCP marking to assign traffic to a specific
hardware forwarding queue (refer to

Using an ACL to change the forwarding queue

on page 139).

For example, the following commands configure an ACL that marks all IP packets with DSCP value 5.
The ACL is then applied to incoming packets on interface 7. Consequently, all inbound packets on
interface 7 are marked with the specified DSCP value.

device(config)#access-list 120 permit ip any any dscp-marking 5 dscp-cos-mapping

device(config)#interface 1/7

device(config-if-e1000-1/7)#ip access-group 120 in

Syntax: dscp-marking dscp-value

The dscp-marking dscp-value parameter marks all traffic to a new DSCP value which can be from 0
through 63.

NOTE
The dscp-cos-mapping option is supported on FSX devices only.

Combined ACL for 802.1p marking

Brocade devices support a simple method for assigning an 802.1p priority value to packets without
affecting the actual packet or the DSCP. In early IronWare software releases, users were required to

Using an IP ACL to mark DSCP values (DSCP marking)

FastIron Ethernet Switch Security Configuration Guide

137

53-1003088-03

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