DCBX operational status is shown as down in Dell EMC networking switches

Summary: As a part of the deployment guidance for Dell EMC Storage Spaces Direct Ready Nodes, for infrastructures that use RoCE v2 for RDMA using Mellanox CX4 LX adapters, we recommend disabling DCBX willing globally in the host OS and setting network adapter DCBXMode to Host in charge. ...

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Symptoms

What is the issue?

After the deployment and configuration of Dell EMC Solution for Microsoft Azure Stack HCI, you may see that the DCBX operational state on the network switches may be shown as down.This can be verified by running

 show interfaces tengigabitethernet x/y pfc detail.

TOR1#show interfaces tengigabitethernet 1/5 pfc detail

Interface TenGigabitEthernet 1/5

Admin mode is on

Admin is enabled, Priority list is 3

Remote is disabled

Local is enabled, Priority list is 3

Oper status is init

PFC DCBX Oper status is Down

Reason: Waiting for Peer

State Machine Type is Symmetric

TLV Tx Status is enabled

PFC Link Delay 65535 pause quntams

Application Priority TLV Parameters :

--------------------------------------

FCOE TLV Tx Status is enabled

ISCSI TLV Tx Status is disabled

Local FCOE PriorityMap is 0x8

Local ISCSI PriorityMap is 0x0

1581 Input TLV pkts, 8649 Output TLV pkts, 121 Error pkts, 4495543 Pause Tx pkts, 374345 Pause Rx pkts

0 Input Appln Priority TLV pkts, 0 Output Appln Priority TLV pkts, 0 Error Appln Priority TLV Pkts

Cause

Where is the issue?

As a part of the deployment guidance for Dell EMC Storage Spaces Direct Ready Nodes, for infrastructures that use RoCE v2 for RDMA using Mellanox CX4 LX adapters, we recommend disabling DCBX willing globally in the host OS and setting network adapter DCBXMode to Host in charge. With this configuration, there is no down stream entity that is exchanging the DCBX information with the Dell EMC networking switch and therefore the DCBX operational status will be shown as down on the server facing ports.

Resolution

This is not a showstopper or an issue of concern. This is working as expected.

Affected Products

Switches
Article Properties
Article Number: 000131009
Article Type: Solution
Last Modified: 30 Jul 2025
Version:  5
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