Understanding the Exhibit and the Problem Statement
The diagram shows a Layer 3 VPN (L3VPN) setup where multiple customers (Customer A, B, and C) are connected across a service provider network using PE (Provider Edge) routers.
PE1 and PE2 exchange VPN routes for all customers using BGP/MPLS Layer 3 VPN (L3VPN) routing.
The question asks how to verify if PE2 is receiving VPN routes for Customer C.
Evaluating the Answer Choices
✅ B. show route table bgp.l3vpn.0 (Correct Answer)
Why?
This command shows all VPN routes stored in the BGP Layer 3 VPN table (bgp.l3vpn.0).
Since PE routers exchange VPN routes using MP-BGP, this table contains the VPN-IPv4 or VPN-IPv6 routes for all customers.
If PE2 is receiving routes from PE1 for Customer C, they will appear in bgp.l3vpn.0.
❌ A. show route table inet.0 (Incorrect)
Why?
The inet.0 table contains global unicast routes for the service provider's network.
VPN routes do not appear here because they are stored in VRF-specific tables.
This command won't help verify VPN route exchange between PE1 and PE2.
❌ C. show route table customer-c.inet.0 (Incorrect)
Why?
The table customer-c.inet.0 represents the VRF routing table for Customer C on the local PE.
It only shows locally installed routes for Customer C but does not confirm if PE2 is receiving routes from PE1.
This command is useful to check local VPN routing but not BGP route propagation.
❌ D. show route summary (Incorrect)
Why?
This command only provides a summary of route counts per protocol (BGP, OSPF, etc.).
It does not display specific VPN routes.
It is useful for general troubleshooting but doesn't confirm VPN route receipt.
Final answer: ✅ show route table bgp.l3vpn.0 (Option B)
Official Juniper Documentation Reference
Junos MPLS VPNs Configuration Guide
Juniper Documentation
"The show route table bgp.l3vpn.0 command displays all VPN-IPv4 routes learned via MP-BGP for Layer 3 VPNs."