Administrator Guide
• PFC enabled or disabled
• No bandwidth limit or no ETS processing
• ETS uses the DCB MIB IEEE 802.1azd2.5.
Data Center Bridging Exchange Protocol (DCBx)
By default, the data center bridging exchange (DCBx) protocol is disabled; ETS is also disabled.
DCBx allows a switch to automatically discover DCB-enabled peers and exchange conguration information. PFC and ETS use DCBx to
exchange and negotiate parameters with peer devices. DCBx capabilities include:
• Discovery of DCB capabilities on peer-device connections.
• Determination of possible mismatch in DCB conguration on a peer link.
• Conguration of a peer device over a DCB link.
DCBx requires the link layer discovery protocol (LLDP) to provide the path to exchange DCB parameters with peer devices. Exchanged
parameters are sent in organizationally specic TLVs in LLDP data units. For more information, see Link Layer Discovery Protocol (LLDP).
The following LLDP TLVs are supported for DCB parameter exchange:
PFC parameters PFC Conguration TLV and Application Priority Conguration TLV.
ETS parameters ETS Conguration TLV and ETS Recommendation TLV.
Data Center Bridging in a Trac Flow
The following gure shows how DCB handles a trac ow on an interface.
Figure 30. DCB PFC and ETS Trac Handling
Data Center Bridging (DCB)
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