Network Router User Manual

42-77
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 42 Configuring PFC QoS
Configuring PFC QoS
When configuring a per-interface policer, note the following information:
• Aggregate policing works independently on each DFC-equipped switching module and
independently on the PFC, which supports any non-DFC-equipped switching modules. Aggregate
policing does not combine flow statistics from different DFC-equipped switching modules. You can
display aggregate policing statistics for each DFC-equipped switching module and for the PFC and
any non-DFC-equipped switching modules supported by the PFC.
• Each PFC or DFC polices independently, which might affect QoS features being applied to traffic
that is distributed across the PFC and any DFCs. Examples of these QoS feature are:
– Policers applied to a port channel interface.
– Policers applied to a switched virtual interface.
– Egress policers applied to either a Layer 3 interface or an SVI. Note that PFC QoS performs
egress policing decisions at the ingress interface, on the PFC or ingress DFC.
Policers affected by this restriction deliver an aggregate rate that is the sum of all the independent
policing rates.
• With a PFC3, when you apply both ingress policing and egress policing to the same traffic, both the
input policy and the output policy must either mark down traffic or drop traffic. PFC QoS does not
support ingress markdown with egress drop or ingress drop with egress markdown.
• With Release 12.2(18)SXE and later releases, you can apply aggregate and microflow policers to
IPv6 traffic.
• With a PFC3, policing uses the Layer 2 frame size.
• With a PFC2, policing uses the Layer 3 packet size.
• See the “PFC QoS Configuration Guidelines and Restrictions” section on page 42-49 for
information about rate and burst size granularity.
• You can enter the flow keyword to define a microflow policer (you cannot apply microflow policing
to ARP traffic). When configuring a microflow policer, note the following information:
– With a PFC3, you can enter the mask src-only keywords to base flow identification only on
source addresses, which applies the microflow policer to all traffic from each source address.
Release 12.2(17d)SXB and later releases support the mask src-only keywords for both IP
traffic and MAC traffic. Releases earlier than Release 12.2(17d)SXB support the mask src-only
keywords only for IP traffic.
– With a PFC3, you can enter the mask dest-only keywords to base flow identification only on
destination addresses, which applies the microflow policer to all traffic to each source address.
Release 12.2(17d)SXB and later releases support the mask dest-only keywords for both IP
traffic and MAC traffic. Releases earlier than Release 12.2(17d)SXB support the mask
dest-only keywords only for IP traffic.
– By default and with the mask full-flow keywords, PFC QoS bases IP flow identification on
source IP address, destination IP address, the Layer 3 protocol, and Layer 4 port numbers.
– With a PFC2, PFC QoS considers IPX traffic with same source network, destination network,
and destination node to be part of the same flow, including traffic with different source nodes
or sockets.
– PFC QoS considers MAC-Layer traffic with the same protocol and the same source and
destination MAC-Layer addresses to be part of the same flow, including traffic with different
EtherTypes.
– Microflow policers do not support the maximum_burst_bytes parameter, the
pir bits_per_second keyword and parameter, or the violate-action keyword.