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Table Of Contents
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 reconfigure dot1p-queue mapping. If the configured dcb-map remains valid, the change
in the dot1p-queue assignment is allowed. For DCB ETS enabled interfaces, traffic 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 field 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 Conflict DCBx version on peer version is different than the local or globally configured DCBx version.
Config-source
Down
Although DCBx parameters match in auto-upstream or auto-downstream port, the configuration source
(elected dynamically or CLI-configured) 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.
Admin Mode OFF
(Remote)
Remote Admin Mode is disabled.
Waiting for ACK
from Peer
For a legacy DCBx version, a peer has not acknowledged the reception of a sent packet. This reason
displays only when a remote peer is willing to receive a DCB configuration.
250 Data Center Bridging (DCB)