Users Guide

NOTE: Dell Networking does not recommend mapping all ingress trac to a single queue when using PFC and ETS. However,
Dell Networking does recommend using Ingress trac classication using the service-class dynamic dot1p command
(honor dot1p) on all DCB-enabled interfaces. If you use L2 class maps to map dot1p priority trac to egress queues, take into
account the default dot1p-queue assignments in the following table and the maximum number of two lossless queues supported
on a port.
Although the system allows you to change the default dot1p priority-queue assignments, DCB policies applied to an interface may
become invalid if you recongure dot1p-queue mapping. If the congured dcb-map remains valid, the change in the dot1p-queue
assignment is allowed. For DCB ETS enabled interfaces, trac destined to queue that is not mapped to any dot1p priority are dropped.
dot1p Value in
the Incoming
Frame
Egress Queue Assignment
0 0
1 0
2 0
3 1
4 2
5 3
6 3
7 3
Troubleshooting PFC, ETS, and DCBx Operation
In the show interfaces pfc | ets | dcbx output, the DCBx operational status may be down for any of the reasons described in
the following table.
When DCBx is down, the following values display in the show output eld for DCBx Oper status:
• PFC DCBx Oper status: Down
• ETS DCBx Oper status: Down
• DCBx Oper status: Disabled.
Reason
Description
Port Shutdown Port is shut down. All other reasons for DCBx inoperation, if any, are ignored.
LLDP Rx/Tx is
disabled
LLDP is disabled (Admin Mode set to rx or tx only) globally or on the interface.
Waiting for Peer Waiting for peer or detected peer connection has aged out.
Multiple Peer
Detected
Multiple peer connections detected on the interface.
Version Conict DCBx version on peer version is dierent than the local or globally congured DCBx version.
Cong-source Down Although DCBx parameters match in auto-upstream or auto-downstream port, the conguration source (elected
dynamically or CLI-congured) is down.
Unrecognized TLV
received
Invalid TLV length TLV has been received. In the case of an invalid PFC or ETS TLV, the error displays in the show
interfaces pfc | ets output. The show interfaces dcbx output displays PFC or ETS as down.
Admin Mode OFF
(Local)
Local Admin Mode is disabled.
Data Center Bridging (DCB) 63