Users Guide

Dell PowerConnect 55xx Systems User Guide 669
• If you bind a policy map to more than one port and one of its classes
contains a single policer, all policy map rules will be multiplied per port
(using up more TCAM resources).
• An aggregate policer applies the QoS to all of its flows in aggregation,
regardless of policies and ports.
Advanced QoS settings consist of the following elements:
• Rules — All frames matching a single group of rules are considered to be a
flow.
• Actions — To be applied to frames in each flow that match the rules.
–
Policers — See "Single Policers" on page 679
–
Aggregate Policers — "Aggregate Policers" on page 677
–
Trust —"Interface Settings" on page 664, "Policy Class Maps" on
page 682
–
Set DSCP/CoS — "Policy Class Maps" on page 682
–
Set Queue — "DSCP Mapping" on page 670
• Binding — Combination of rules and actions that are bound to one or
more interfaces.
Workflow to Configure Advanced QoS Mode
To configure Advanced QoS mode, perform the following:
1
Select Advanced mode for the system in the QoS Mode page .
2 If external DSCP values are different from those used on incoming
packets, map the external values to internal values in the
DSCP Rewrite
page.
3 Create ACLs, as described in "Network Security" on page 92.
4 When ACLs are defined, create class maps and associate the ACLs with
them in the
Class Mapping pages .
5 Create a policy map in the Policy Class Maps pages, and associate the
policy map with one or more class maps. Specify the QoS action, if needed,
for example by assigning a policer to a class map, when you associate the
class map to the policy.