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Table of Contents
- play_arrow Basic CoS Configuration
- play_arrow CoS Overview
- play_arrow CoS on Interfaces
- play_arrow CoS Code-Point Aliases
- play_arrow CoS Classifiers
- Understanding CoS Classifiers
- Defining CoS BA Classifiers (DSCP, DSCP IPv6, IEEE 802.1p)
- Example: Configuring Classifiers
- Example: Configuring Unicast Classifiers
- Example: Configuring Multidestination (Multicast, Broadcast, DLF) Classifiers
- Understanding Host Inbound Traffic Classification
- Configuring a Global MPLS EXP Classifier
- Monitoring CoS Classifiers
- play_arrow CoS Rewrite Rules
- Understanding CoS Rewrite Rules
- Defining CoS Rewrite Rules
- Understanding Applying CoS Classifiers and Rewrite Rules to Interfaces
- Troubleshooting an Unexpected Rewrite Value
- Understanding CoS MPLS EXP Classifiers and Rewrite Rules
- Configuring Rewrite Rules for MPLS EXP Classifiers
- Monitoring CoS Rewrite Rules
- play_arrow CoS Forwarding Classes and Forwarding Class Sets
- Understanding CoS Forwarding Classes
- Defining CoS Forwarding Classes
- Forwarding Policy Options Overview
- Configuring CoS-Based Forwarding
- Example: Configuring CoS-Based Forwarding
- Example: Configuring Forwarding Classes
- Understanding CoS Forwarding Class Sets (Priority Groups)
- Defining CoS Forwarding Class Sets
- Example: Configuring Forwarding Class Sets
- Monitoring CoS Forwarding Classes
- play_arrow Lossless Traffic Flows, Ethernet PAUSE Flow Control, and PFC
- Understanding CoS IEEE 802.1p Priorities for Lossless Traffic Flows
- Configuring CoS PFC (Congestion Notification Profiles)
- Understanding CoS Flow Control (Ethernet PAUSE and PFC)
- Enabling and Disabling CoS Symmetric Ethernet PAUSE Flow Control
- Configuring CoS Asymmetric Ethernet PAUSE Flow Control
- Understanding PFC Functionality Across Layer 3 Interfaces
- Example: Configuring PFC Across Layer 3 Interfaces
- Understanding PFC Using DSCP at Layer 3 for Untagged Traffic
- Configuring DSCP-based PFC for Layer 3 Untagged Traffic
- play_arrow CoS and Host Outbound Traffic
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- play_arrow Weighted Random Early Detection (WRED) and Explicit Congestion Notification (ECN)
- play_arrow WRED and Drop Profiles
- play_arrow Explicit Congestion Notification (ECN)
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- play_arrow Data Center Bridging and Lossless FCoE
- play_arrow Data Center Bridging
- Understanding DCB Features and Requirements
- Understanding DCBX
- Configuring the DCBX Mode
- Configuring DCBX Autonegotiation
- Understanding DCBX Application Protocol TLV Exchange
- Defining an Application for DCBX Application Protocol TLV Exchange
- Configuring an Application Map for DCBX Application Protocol TLV Exchange
- Applying an Application Map to an Interface for DCBX Application Protocol TLV Exchange
- Example: Configuring DCBX Application Protocol TLV Exchange
- play_arrow Lossless FCoE
- Example: Configuring CoS PFC for FCoE Traffic
- Example: Configuring CoS for FCoE Transit Switch Traffic Across an MC-LAG
- Example: Configuring CoS Using ELS for FCoE Transit Switch Traffic Across an MC-LAG
- Example: Configuring Lossless FCoE Traffic When the Converged Ethernet Network Does Not Use IEEE 802.1p Priority 3 for FCoE Traffic (FCoE Transit Switch)
- Example: Configuring Two or More Lossless FCoE Priorities on the Same FCoE Transit Switch Interface
- Example: Configuring Two or More Lossless FCoE IEEE 802.1p Priorities on Different FCoE Transit Switch Interfaces
- Example: Configuring Lossless IEEE 802.1p Priorities on Ethernet Interfaces for Multiple Applications (FCoE and iSCSI)
- Troubleshooting Dropped FCoE Traffic
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- play_arrow CoS Buffers and the Shared Buffer Pool
- play_arrow CoS Buffers Overview
- play_arrow Shared Buffer Pool Examples
- Example: Recommended Configuration of the Shared Buffer Pool for Networks with Mostly Best-Effort Unicast Traffic
- Example: Recommended Configuration of the Shared Buffer Pool for Networks with Mostly Best-Effort Traffic on Links with Ethernet PAUSE Enabled
- Example: Recommended Configuration of the Shared Buffer Pool for Networks with Mostly Multicast Traffic
- Example: Recommended Configuration of the Shared Buffer Pool for Networks with Mostly Lossless Traffic
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- play_arrow CoS on EVPN VXLANs
- play_arrow Configuration Statements and Operational Commands
list Table of Contents
Troubleshooting Egress Queue Bandwidth Impacted by Congestion
date_range
18-Feb-21
Problem
Description
Congestion on an egress port causes egress queues to receive less bandwidth than expected. Egress port congestion can impact the amount of bandwidth allocated to queues on the congested port and, in some cases, on ports that are not congested.
Cause
Egress queue congestion can cause the ingress port buffer to fill above a certain threshold and affect the flow to the queues on the egress port. One queue receives its configured bandwidth, but the other queues on the egress port are affected and do not receive their configured share of bandwidth.
Solution
The solution is to configure a drop profile to apply weighted random early detection (WRED) to the queue or queues on the congested ports.
Configure a drop profile on the queue that is receiving its configured bandwidth. This queue is preventing the other queues from receiving their expected bandwidth. The drop profile prevents the queue from affecting the other queues on the port.
To configure a WRED profile using the CLI:
Name the drop profile and set the drop start point, drop end point, minimum drop rate, and maximum drop rate for the drop profile:
content_copy zoom_out_map[edit class-of-service] user@switch# set drop-profile drop-profile-name interpolate fill-level percentage fill-level percentage drop-probability 0 drop-probability percentage
