Cisco WS-X6066-SLB-APC - Content Switching Module Software Manual page 741

Chapter 41 Configuring QoS
The burst parameter sets the token bucket size. To sustain a specific rate, set the token bucket size
Note
with the burst parameter to be at least the rate divided by 4000, because tokens are removed from
the bucket every 1/4000th of a second (0.25 ms) and the bucket needs to be at least burst-size long
to sustain the specified rate.
Because any packet larger than the burst size is considered an out-of-profile packet, make sure that
Note
the burst size is greater than or equal to the largest packet size of the policer that is applied to it.
QoS programs the hardware with values that are multiples of 32K (32,768), not with the specific
Note
value entered.
Enter either the drop keyword to cause all out-of-profile packets to be dropped or the policed-dscp
keyword to cause all out-of-profile packets with the normal rate to be marked down as specified in the
normal markdown DSCP map (for more information, see the
section on page
This example shows how to create a microflow policing rule with a 1-Mbps rate limit and a 10-Mb burst
limit that marks down out-of-profile traffic:
Console> (enable) set qos policer microflow my-micro rate 1000 burst 10000
policed-dscp
Hardware programming in progress...
QoS policer for microflow my-micro created successfully.
Console> (enable)
For PFC2, this example shows how to create an aggregate excess rate policing rule with a 64-Kbps rate
limit and a 128-Kb burst limit that drops traffic exceeding these values:
Console> (enable) set qos policer aggregate test rate 64 burst 128 drop
QoS policer for aggregate test created successfully.
Console> (enable) show qos policer config aggregate test
QoS aggregate policers:
QoS aggregate policers:
Aggregate name
----------------------------- ------------------ --------------- -------------
test
------------------------------------
Console> (enable)
For PFC2, this example shows how to create an aggregate excess rate policing rule with a 64-Kbps rate
limit and a 100-Kb burst limit that will cause all out-of-profile packets to be marked down as specified
in the normal markdown DSCP map:
Console> (enable) set qos policer aggregate test2 rate 64 burst 100 policed-dscp
QoS policer for aggregate test2 created successfully.
78-13315-02
41-57).
Normal rate (kbps) Burst size (kb) Normal action
Excess rate (kbps) Burst size (kb) Excess action
------------------ --------------- -------------
ACL attached
Catalyst 6000 Family Software Configuration Guide—Releases 6.3 and 6.4
"Mapping DSCP Markdown Values"
64 128 policed-dscp
64 128 drop
Configuring QoS
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