Which two statements correctly describe an ESI-LAG? (Choose two.)

Question

Options

• ABoth VTEPs advertise connectivity to the same Ethernet segment.
• BBoth VTEPs advertise connectivity to different Ethernet segments.
• CThe LACP system ID on the two connected leafs is configured with the same value.
• DThe LACP system ID on the two connected leafs is configured with different values.

• A
  73% (19)
• B
  19% (5)
• D
  8% (2)

Explanation

In an ESI-LAG, a host is multi-homed to two VTEPs that share the same Ethernet Segment Identifier (ESI). Because they share that ESI, both VTEPs advertise reachability to the same Ethernet segment via EVPN BGP (A is correct). For the connected device to form a single LAG across both uplinks, it must believe it is speaking to one logical switch - which requires both leafs to present the same LACP System ID (C is correct); otherwise the end device sees two independent switches and cannot bundle the links into one LAG.

B is wrong because advertising different Ethernet segments is the opposite of what ESI-LAG does - the entire purpose of sharing an ESI is to represent the same segment from two VTEPs.

D is wrong because mismatched LACP System IDs would break the LAG from the connected device's perspective; it would treat each uplink as belonging to a separate partner switch.

Memory tip: ESI-LAG is about making two VTEPs look like one - same ESI, same LACP System ID, same advertised segment. When in doubt, ask "does this make them look identical to the connected device?" If yes, it's correct for ESI-LAG.

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