H12-891_V1.0 Exam Dumps : HCIE-Datacom V1.0

There arethree standard inter-AS MPLS VPN options, as per RFC 4364:

Option A (Back-to-Back VRF):

VRFs are directly connected between ASBRs using routing exchange (like static/BGP).

No label switching between ASs —no MPLS label neededbetween ASs.

Option B (EBGP Label Exchange):

ASBRs exchange labeled VPNv4 routes via EBGP.

One MPLS label is required —MPLS forwarding across AS boundaryis used.

Option C (End-to-End LSP):

Full end-to-end LSP is created across ASs.

MPLS labels are definitely usedend-to-end, even between ASs.

Option D (Commonly vendor-specific extensions based on Option B/C):

Similar to Option C —requires MPLS labels.

So:

B. Option B— needs MPLS label✅

D. Option D— also needs MPLS label✅

A. Option A—no MPLS label❌

C. Option C— also uses MPLS label✅, but not listed as an answer option in this question format (should have been).

Assuming valid options areA, B, D, the correct ones needing MPLS labels are:

Correct answers: B, D

The command port-isolate enable is used on Huawei switches to completely isolate traffic at both Layer 2 and Layer 3 between different interfaces within the same VLAN. This isolation prevents any communication between isolated ports—even if they belong to the same subnet or VLAN—making it a critical security feature in multi-tenant environments.

Usage Context:

Often used in shared service or hotel network scenarios.

Can be applied in access port configurations.

Does not require additional VLAN creation or private VLAN features.

Huawei Datacom Reference:

"To completely isolate Layer 2 and Layer 3 communication between interfaces in the same VLAN, run the port-isolate enable command under the interface view."

(Source: HCIE-Datacom Study Guide V3.0 – Chapter: VLAN & Security Technologies, Section: Port Isolation)

To automatically enable MPLS on an interface inSR-MPLS:

Segment routing must be enabled globallyin thesystem view→✅

Segment routing must also be enabled under the IGP process, andIGP (OSPF or IS-IS) must be enabled on the interface→✅

Clarifications:

SRGB (Segment Routing Global Block)configuration defines SID ranges butdoes not trigger MPLS enablement→❌

Static adjacency labelsare advanced options and do not auto-enable MPLS →❌

Correct answers: B, D