Refer to the exhibit. An engineer is trying to configure an EVPN VWPS. What is the issue with this configuration?

Question

Exhibit

Options

• AThe member in the VPWS context should be the PE-facing interface.
• BThe 12vpn evpn command should be instance 101.
• CInterface GigabitEthernet0/1/0 should not have any IP address.
• DThe service instance and the EVPN instance are different.

• A
  3% (1)
• B
  10% (3)
• C
  80% (24)
• D
  7% (2)

Explanation

In EVPN VPWS (Virtual Private Wire Service), the attachment circuit interface acts as a raw Layer 2 handoff - it extends an Ethernet "wire" between two PE routers. Assigning an IP address to GigabitEthernet0/1/0 converts it into a Layer 3 routed interface, which breaks the L2 forwarding behavior that VPWS depends on. The interface must be a pure L2 port (no IP) so that Ethernet frames are passed transparently across the EVPN pseudowire.

Why the distractors are wrong:

• A is incorrect because in a standard EVPN VPWS config, the VPWS context member correctly points to the service instance on the CE-facing (attachment circuit) interface - this part of the config is typically valid.
• B is incorrect because the l2vpn evpn instance number is a locally significant identifier; there is no universal rule requiring it to be instance 101.
• D is a common trap - the service instance ID and the EVPN instance ID do not have to match each other; they serve different purposes (one identifies the EFP, the other identifies the EVPN binding).

Memory tip: Think "VPWS = Wire = Layer 2 only." If you see an IP address on an attachment circuit interface in a VPWS question, that's always the red flag - wires don't have IP addresses.

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