Chapter 6
Policing Traffic
If you upgrade from a Cisco IOS software release that does not support dual police actions to a
Cisco IOS release that supports dual police actions, the police command displays on a single line. If you
configure each police action on a separate line and then downgrade to a Cisco IOS release that does not
support dual actions, the router rejects the policer.
For backward compatibility, the router accepts the police command on a single line, but after entering
the police command, the router enters policy-map-class-police configuration mode.
Feature History for Dual Police Actions
Cisco IOS Release
Release 12.2(33)SB
Policing Support for GRE Tunnels
The Policing Support for GRE Tunnels feature allows you to set the Differentiated Services Code Point
(DSCP) and IP precedence values on Generic Routing Encapsulation (GRE) tunnel packets.
This feature is essential for MPLS carriers to offer QoS on Multicast VPN services. Multicast VPN
(MVPN) uses GRE tunnels between PE devices, and multicast packets are placed in GRE tunnels for
transmission across the MPLS core network. The Policing Support for GRE Tunnels feature allows the
GRE tunnel to reflect the underlying QoS of the multicast packets. Once the GRE packets accurately
reflect the QoS markings of the underlying multicast packets, they may be queued accordingly as they
travel across the core nodes.
For more information, see the Policing Support for GRE Tunnels, Release 12.2(31)SB2 feature module
and the
Interfaces Supporting Policing
The following describes interface support for policing using the police command:
Interfaces Supporting the police Command
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OL-7433-09
Description
This feature was introduced on the router for the PRE3 and
PRE4.
"Tunnel Header Marking" section on page
Physical
Multilink PPP and multilink Frame Relay
ATM unspecified bit rate (UBR) PVCs and point-to-point subinterfaces
ATM variable bit rate (VBR) and constant bit rate (CBR) PVCs, and point-to-point subinterfaces
Label-controlled ATM (LC-ATM) subinterfaces
Frame Relay permanent virtual circuits (PVCs), point-to-point subinterfaces, and map classes
Ethernet VLANs
IP tunnel
Virtual-access (See the
"VAI QoS Inheritance" section on page
7-18.
Cisco 10000 Series Router Quality of Service Configuration Guide
Policing Support for GRE Tunnels
Required PRE
PRE3, PRE4
4-24.)
6-17