AutoQoS Enterprise Router Platforms

This topic describes the router platforms on which AutoQoS can be used.

The figure shows the listed Cisco router platforms that support the AutoQoS Enterprise feature. When verifying whether the Cisco IOS software Release 12.3(7)T supports AutoQoS Enterprise, check the Cisco Feature Navigator tool on the Cisco.com website.

Step 2: Select QoS Mechanisms

What Qos Mechanism

When searching for a Cisco IOS software version that will support the AutoQoS Enterprise feature, make sure, when using the Cisco IOS Feature Navigator tool, that you select these two options, as indicated in the "Features available" list shown in the figure:

■ AutoQoS for the Enterprise - Suggested Policy: Discovers and automatically configures QoS policies for application traffic.

■ AutoQoS: AutoDiscovery Trust Option: Extends the power of Cisco AutoQoS Enterprise to those routers on which differentiated services code point (DSCP) values have already been assigned to traffic at the network edge. This option enables customers to automatically set the QoS policy on routers by allowing the network to trust internally established priority levels for various types of traffic.

This topic describes the prerequisites for configuring AutoQoS Enterprise.

This topic describes the prerequisites for configuring AutoQoS Enterprise.

Before configuring AutoQoS on a Cisco router, you must meet these prerequisites:

■ Removal of any preexisting service policies.

■ Cisco Express Forwarding (CEF) must be enabled at the interface level on ATM PVC or Frame Relay DLCIs (point-to-point subinterfaces only).

■ AutoQoS uses network-based application recognition (NBAR) to identify various applications and traffic types, and CEF is a prerequisite for NBAR.

■ AutoQoS classifies links as either low-speed or high-speed, depending upon the link bandwidth. If the default bandwidth is not specified on a serial connection, it is 1.544 Mbps. You must specify the correct bandwidth on the interface or subinterface where AutoQoS is to be enabled, as follows:

— For all interfaces or subinterfaces, be sure to properly configure the bandwidth by using the bandwidth command. The amount of bandwidth that is allocated should be based on the link speed of the interface.

— If the interface or subinterface has a link speed of 768 kbps or lower, an IP address must be configured on the interface or subinterface using the ip address command. By default, AutoQoS will enable Multilink PPP (MLP) and copy the configured IP address to the multilink bundle interface.

In addition to the AutoQoS prerequisites, there are other recommendations and requirements when configuring AutoQoS, as follows: (Be aware that these may change with Cisco IOS

releases and should be verified before implementing AutoQoS in the environment.)

■ The AutoQoS Enterprise feature is supported only on the following interfaces and PVCs:

— ATM PVCs low and high speed subinterfaces only

— Serial interfaces with PPP or high-level data link control (HDLC)

— Frame Relay DLCIs (point-to-point subinterfaces only)

■ AutoQoS does not support Frame Relay multipoint interfaces

■ You can manually tune a configuration template, generated by configuring AutoQoS on an interface or PVC, via a command-line interface (CLI), if desired.

■ AutoQoS cannot be configured if a QoS service policy is already configured and attached to the interface or PVC.

■ MLP is configured automatically for a serial interface with a low-speed link when RealTime Transport Protocol (RTP) traffic is detected. The serial interface must have an IP address, which is removed and put on the MLP bundle. AutoQoS Enterprise must also be configured on the other side of the link.

■ The no auto discovery qos command removes auto discovery on WAN interfaces.

■ The no auto qos voip command removes AutoQoS VoIP. However, if the interface or PVC on which AutoQoS generated QoS configuration is deleted without configuring the no auto qos voip command, AutoQoS VoIP will not be completely removed from the configuration.

■ AutoQoS Simple Network Management Protocol (SNMP) traps are only delivered when an SNMP server is used in conjunction with AutoQoS.

■ The SNMP community string "AutoQoS" should have "write" permission.

■ If the device is reloaded with the saved configuration after configuring AutoQoS and saving the configuration to NVRAM, some warning messages may be generated by Remote Monitoring (RMON) threshold commands. You can ignore these warning messages. (To avoid further warning messages, save the configuration to NVRAM again without making any changes to the QoS configuration.)

■ By default, Cisco 7200 series routers and below that support Modular QoS CLI (MQC) reserve up to 75 percent of the interface bandwidth for user-defined classes. The remaining bandwidth is used for the default class. However, the entire remaining bandwidth is not guaranteed to the default class. This bandwidth is shared proportionally between the different flows in the default class and excess traffic from other bandwidth classes. By default, at least one percent of the available bandwidth is reserved and guaranteed for class default traffic on Cisco 7500 series routers. (You can allocate up to 99 percent to the other classes.)

Mark Routes Coming from AS 73

To configure AutoQoS Enterprise, enter auto discovery qos [trust] first, and then, after two to three days and after the verification of traffic statistics, add the auto qos commands on a router WAN interface. To verify that traffic has been gathered, enter show auto discovery qos [interface]. The router will not accept the auto qos command until statistics have been gathered.

Note Configuring auto qos voip along with auto discovery qos [trust] defaults the AutoQoS

policy generation to AutoQoS VoIP.

To remove the AutoQoS discovery or AutoQoS VoIP feature from an interface, use the no form of the auto discovery qos or auto qos voip commands:

no auto discovery qos [trust] no auto qos

Syntax Description

Command

Description

auto discovery qos [trust]

Begins discovering and collecting data for configuring the AutoQoS for the Enterprise feature.

The [trust] option indicates that the DSCP markings of a packet are trusted; that is, used for classification of the voice, video, and data traffic.

If the optional [trust] keyword is not specified, the voice, video, and data traffic is classified using NBAR, and the packets are marked with the appropriate DSCP value.

auto qos

Installs the QoS class maps and policy maps created by the AutoQoS for the Enterprise feature.

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