Administrator Guide

Dot1p Priority Queue
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Default dot1p to queue configuration is as follows:
Configuration Example for DSCP and PFC
Priorities
Consider a scenario in which the following DSCP and PFC priorities are necessary:
DSCP 0 – 5, 10 - 15 20 – 25, 30 – 35
Expected PFC
Priority
1 2
To configure the aforementioned DSCP and PFC priority values, perform the following tasks:
1. Create class-maps to group the DSCP subsets
class-map match-any dscp-pfc-1
match ip dscp 0-5,10-15
!
class-map match-any dscp-pfc-2
match ip dscp 20-25,30-35
2. Associate above class-maps to Queues Queue assignment as below.
DellEMC(conf)#do show qos dot1p-queue-mapping
Dot1p Priority : 0 1 2 3 4 5 6 7
Queue : 1 0 2 3 4 5 6 7
3. Dot1p->Queue Mapping Configuration is retained at the default value.
4. Interface Configurations on server connected ports.
a. Enable DCB globally.
DellEMC(conf)#dcb enable
b. Apply PFC Priority configuration. Configure priorities on which PFC is enabled.
Using PFC to Manage Converged Ethernet Traffic
To use PFC for managing converged Ethernet traffic, use the following command:
dcb-map stack-unit all dcb-map-name
Generation of PFC for a Priority for Untagged
Packets
In order to generate PFC for a particular priority for untagged packets, and configuring PFC for that priority, you should find the queue
number associated with priority from TABLE 1 and Associate a DCB map to forward the matched DSCP packet to that queue. PFC frames
gets generated with PFC priority associated with the queue when the queue gets congested.
Configure Enhanced Transmission Selection
ETS provides a way to optimize bandwidth allocation to outbound 802.1p classes of converged Ethernet traffic.
Different traffic types have different service needs. Using ETS, you can create groups within an 802.1p priority class to configure different
treatment for traffic with different bandwidth, latency, and best-effort needs.
Data Center Bridging (DCB)
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