Administrator Guide
NOTE: Because DCBx TLV processing is best eort, it is possible that CIN frames may be processed when DCBx is
congured to operate in CEE mode and vice versa. In this case, the unrecognized TLVs cause the unrecognized TLV
counter to increment, but the frame is processed and is not discarded.
Legacy DCBx (CIN and CEE) supports the DCBx control state machine that is dened to maintain the sequence number and
acknowledge the number sent in the DCBx control TLVs.
DCBx Example
The following gure shows how DCBX is used on an MXL Switch installed in a PowerEdge M1000e chassis in which servers are also
installed.
The external 40GbE ports on the base module (ports 33 and 37) of two switches are used for uplinks congured as DCBx auto-
upstream ports. The MXL switch is connected to third-party, top-of-rack (ToR) switches through 40GbE uplinks. The ToR switches
are part of a Fibre Channel storage network.
The internal ports (ports 1-32) connected to the 10GbE backplane are congured as auto-downstream ports.
On the MXL switch, PFC and ETS use DCBx to exchange link-level conguration with DCBx peer devices.
Figure 144. DCBx Sample Topology
FC Flex IO Modules
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