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QoS rate adjustment is disabled by default.
•
Specify the number of bytes of packet overhead to include in rate limiting, policing, and shaping calculations.
CONFIGURATION mode
qos-rate-adjust
overhead-bytes
For example, to include the Preamble and SFD, type
qos-rate-adjust 8
. For variable length overhead fields, know the
number of bytes you want to include.
The default is disabled.
The range is from 1 to 31.
Enabling Strict-Priority Queueing
In strict-priority queuing, the system de-queues all packets from the assigned queue before servicing any other queues. You can
assign strict-priority to one unicast queue, using the strict-priority command.
•
Policy-based per-queue rate shaping is not supported on the queue configured for strict-priority queuing. To use queue-based
rate-shaping as well as strict-priority queuing at the same time on a queue, use the Scheduler Strict feature as described in
Scheduler Strict .
•
The
strict-priority
supersedes
bandwidth-percentage
configuration.
•
A queue with strict priority can starve other queues in the same port-pipe.
•
Assign strict priority to one unicast queue.
CONFIGURATION mode
strict-priority
The range is from 1 to 3.
Weighted Random Early Detection
Weighted random early detection (WRED) is a congestion avoidance mechanism that drops packets to prevent buffering resources
from being consumed.
The WRED congestion avoidance mechanism drops packets to prevent buffering resources from being consumed.
Traffic is a mixture of various kinds of packets. The rate at which some types of packets arrive might be greater than others. In this
case, the space on the buffer and traffic manager (BTM) (ingress or egress) can be consumed by only one or a few types of traffic,
leaving no space for other types. You can apply a WRED profile to a policy-map so that specified traffic can be prevented from
consuming too much of the BTM resources.
WRED uses a profile to specify minimum and maximum threshold values. The minimum threshold is the allotted buffer space for
specified traffic, for example, 1000KB on egress. If the 1000KB is consumed, packets are dropped randomly at an exponential rate
until the maximum threshold is reached (as shown in the following illustration); this procedure is the “early detection” part of WRED.
If the maximum threshold, for example, 2000KB, is reached, all incoming packets are dropped until the buffer space consumes less
than 2000KB of the specified traffic.
Quality of Service (QoS)
693
Содержание S4048-ON
Страница 1: ...Dell Configuration Guide for the S4048 ON System 9 9 0 0 ...
Страница 146: ...Figure 14 BFD Three Way Handshake State Changes 146 Bidirectional Forwarding Detection BFD ...
Страница 477: ...Figure 68 Inspecting Configuration of LAG 10 on ALPHA Link Aggregation Control Protocol LACP 477 ...
Страница 480: ...Figure 70 Inspecting a LAG Port on BRAVO Using the show interface Command 480 Link Aggregation Control Protocol LACP ...
Страница 481: ...Figure 71 Inspecting LAG 10 Using the show interfaces port channel Command Link Aggregation Control Protocol LACP 481 ...
Страница 522: ...Figure 87 Configuring Interfaces for MSDP 522 Multicast Source Discovery Protocol MSDP ...
Страница 523: ...Figure 88 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 523 ...
Страница 524: ...Figure 89 Configuring PIM in Multiple Routing Domains 524 Multicast Source Discovery Protocol MSDP ...
Страница 528: ...Figure 91 MSDP Default Peer Scenario 1 528 Multicast Source Discovery Protocol MSDP ...
Страница 529: ...Figure 92 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 529 ...
Страница 530: ...Figure 93 MSDP Default Peer Scenario 3 530 Multicast Source Discovery Protocol MSDP ...
Страница 633: ...Policy based Routing PBR 633 ...
Страница 777: ...Figure 119 Single and Double Tag TPID Match Service Provider Bridging 777 ...
Страница 778: ...Figure 120 Single and Double Tag First byte TPID Match 778 Service Provider Bridging ...