Setup Guide
The packets come in with packet-dot1p 2 alone use Q1 (as per dot1p to Queue classication – Table 2) on the egress port.
• When Peer sends a PFC message for Priority 2, based on above PRIO2COS table (TABLE 2), Queue 1 is halted.
• Queue 1 starts buering the packets with Dot1p 2. This causes PG6 buer counter to increase on the ingress, since P-dot1p 2 is
mapped to PG6.
• As the PG6 watermark threshold is reached, PFC generates for dot1p 2.
Conguration 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 congure 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.
Table 19. Queue Assignments
Internal-priority Queue
0 0
1 0
2 0
3 1
4 2
5 3
6 3
7 3
3 Dot1p->Queue Mapping Conguration is retained at the default value.
4 Interface Congurations on server connected ports.
a Enable DCB globally.
DellEMC(conf)#dcb enable
b Apply PFC Priority conguration. Congure priorities on which PFC is enabled.
Data Center Bridging (DCB)
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