Dynamically Changing Vc Weight And Watermark Values - Cisco 10000 Series Configuration Manual

Dynamically Changing VC Weight and Watermark Values

Command
Router# debug ppp negotiation
Router# debug radius
Router# debug vpdn event
Router# debug vpdn 12x-errors
Router# debug vpdn 12x-events
Router# debug vpdn pppoe-errors
Router# debug vpdn pppoe-events
Dynamically Changing VC Weight and Watermark Values
The DBS Extensions—VC Weight and Watermarks feature extends the capability of the Dynamic
Bandwidth Selection (DBS) feature to enable you to dynamically change the existing VC weight and
watermark values applied to a session without tearing down the VC and then recreating it. This
eliminates the need to statically configure each subscriber's VC using the modular QoS command line
interface (MQC). As a result, you can save configuration time, reduce the size and complexity of the
router's configuration file, and reduce the time required for router initialization after planned or
unplanned outages.
The VC weight value indicates the number of cells that a VC can send to the virtual path (VP) tunnel
before the line card segmentation and reassembly (SAR) mechanism processes the next VC. A high
weight value has a higher VC priority in the VP scheduler than a VC with a low weight value.
The high and low watermark values define the depth of the PVC interface queue on the line card. The
SAR mechanism on ATM line cards creates a queue for every configured PVC. Each PVC queue has a
high and low watermark that defines the number of cells a queue can hold.
DBS operates with authentication, authorization, and accounting (AAA) servers (such as RADIUS) to
provide ATM VC parameters to the router. To dynamically retrieve VC weight and watermark
parameters from RADIUS, the following Cisco attribute value (AV) pairs are defined on the RADIUS
server:
cisco-avpair = "atm:vc-weight=<weight value>"
cisco-avpair = "atm:vc-watermark-min=<minimum watermark value>"
cisco-avpair = "atm:vc-watermark-max=<maximum watermark value>"
Note Valid VC weight values are from 1 to 255. However, we recommend that you do not configure the value
below 5.
Cisco 10000 Series Router Quality of Service Configuration Guide
17-18
Chapter 17
Purpose
Enables debugging of the PPP negotiation process.
Displays detailed debugging information associated with
RADIUS.
Displays L2TP errors and events that are a part of normal tunnel
establishment or shutdown for VPDNs.
Displays L2TP protocol errors that prevent tunnel establishment
or normal operation.
Displays L2TP events that are part of tunnel establishment or
shutdown.
Displays PPPoE protocol errors that prevent a session from being
established or errors that cause an established session to be
closed.
Displays PPPoE protocol messages about events that are part of
normal session establishment or shutdown.
Configuring Dynamic Subscriber Services
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