Configuration Guide User guide

1742 FastIron Configuration Guide
53-1002494-02
QoS options for IP ACLs
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 1743).
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.
Brocade(config)#access-list 120 permit ip any any dscp-marking 5 dscp-cos-mapping
Brocade(config)#interface 1/7
Brocade(config-if-e1000-1/7)#ip access-group 120 in
Syntax: ...dscp-marking <dscp-value>
The dscp-marking <dscp-value> parameter maps a DSCP value to an internal forwarding priority.
The DSCP value can be from 0 – 63.
NOTE
The dscp-cos-mapping option is supported on FESX and 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 provide DSCP-marking and DSCP-matching information in order to assign 802.1p priority values,
which required the deployment of a 64-line ACL to match all possible DSCP values. Users were also
required to configure an internal priority marking value. Now, users can easily specify 802.1p
priority marking values directly, and change internal priority marking from required to optional.
NOTE
This feature is not applicable to outbound traffic.
On the following devices, if the user does not set a specific internal marking priority, the default
value is the same as the 802.1-priority marking value:
• FWS, FCX, FESX, and ICX devices
• FastIron SX modules, with the exception of SX-48GCPP modules, released prior to hardware
release 07.3.00, including:
• SX-FI624C
• SX-FI624HF
• SX-FI62XG
• SX-FI42XG
• SX-FI424C
• SX-FI424F
• SX-FI8GMR6
• SX-FI2XGMR4
On the following devices, if the user does not set a specific internal marking priority, then the
internal priority does not change: