JN0-664 Exam Dumps : Service Provider Professional (JNCIP-SP)

Analyzing the Exhibit and Understanding the Issue

The exhibit shows BGP configurations on CE-1 and PE-1, which are connected via EBGP.

CE-1 (Customer Edge)

Uses AS 64511 and establishes an EBGP session with PE-1 (AS 65550).

Configured to export 10 static routes (192.168.1.0/24 - 192.168.10.0/24) using the static-to-bgp policy.

PE-1 (Provider Edge)

Uses AS 65550 and is peering with CE-1 (AS 64511).

Configured with a prefix-limit of 5 on received routes from CE-1.

Teardown enabled, meaning if more than 5 prefixes are received, the BGP session is shut down.

Identifying the Problem

CE-1 is correctly configured with peer AS 65550, so Option B ("CE-1 is configured with an incorrect peer AS") is incorrect ❌.

CE-1 is advertising exactly 10 static routes (as per policy).

PE-1 has a prefix-limit maximum 5 with teardown enabled.

This means that when CE-1 advertises more than 5 prefixes, PE-1 shuts down the BGP session.

BGP moves to the "Active" state, indicating that the session has been disrupted and PE-1 is trying to re-establish the connection.

CE-1 is reachable since the session was initially established before the limit was exceeded, so Option D ("CE-1 is unreachable") is incorrect ❌.

CE-1 is not advertising its entire routing table, only the static prefixes listed in the policy, so Option A ("CE-1 is advertising its entire routing table") is incorrect ❌.

Correct Answer

✅ C. The prefix limit has been reached on PE-1

Verification from Juniper Documentation

Juniper BGP Prefix Limit Documentation confirms that exceeding the prefix limit with teardown causes the BGP session to go into "Active" state.

Juniper Troubleshooting Guide for BGP Peering Issues states that when a BGP session reaches the prefix limit and has teardown enabled, the session is terminated.

In the provided exhibit, the output of the `show pim join extensive 232.1.1.1` command is shown. This command provides detailed information about the PIM join state for the specified multicast group (232.1.1.1) on the router R1. To determine the correct statements regarding the multicast traffic, let's analyze the output and the terms involved:

1. **ASM vs. SSM**:

- **ASM (Any-Source Multicast)**: In ASM, receivers are interested in receiving multicast traffic from any source sending to a particular multicast group.

- **SSM (Source-Specific Multicast)**: In SSM, receivers are interested in receiving traffic only from specific sources for a multicast group.

- **Group Address Range**:

- ASM uses the range 224.0.0.0 to 239.255.255.255.

- SSM uses the range 232.0.0.0 to 232.255.255.255.

Since the group address 232.1.1.1 falls within the SSM range (232.0.0.0/8), there might be confusion. However, considering the flags and states in the output, it's evident that the PIM mode and source information are consistent with ASM behavior.

2. **Multicast Trees**:

- **RPT (Rendezvous Point Tree)**: Multicast traffic initially uses the RPT, where the Rendezvous Point (RP) acts as an intermediate point.

- **SPT (Shortest Path Tree)**: After the initial join via RPT, traffic can switch to SPT, which is a direct path from the source to the receiver.

3. **Output Analysis**:

- **Flags**:

- The flags `sparse, rp-tree, wildcard` indicate that the group 232.1.1.1 is currently using RPT. This is typical for ASM, where traffic initially goes through the RP.

- The flags `sparse, spt` indicate that for the source 172.16.1.2, traffic has switched to SPT, meaning it is using the shortest path from the source directly to the receivers.

**Conclusion**:

Based on the analysis:

- **A. The multicast group is an ASM group**: This statement is correct as the configuration and behavior indicate ASM operation.

- **B. The multicast traffic is using the SPT**: This statement is also correct because the flags for the source 172.16.1.2 indicate that the traffic is using the SPT.

Thus, the correct answers are:

**A. The multicast group is an ASM group.**

**B. The multicast traffic is using the SPT.**

**References**:

- Juniper Networks PIM Documentation: [PIM

- Junos OS Multicast Routing Configuration Guide: [Multicast Routing Configuration

The exhibit shows the configuration of a VRF (Virtual Routing and Forwarding) instance on a Juniper PE router. Let's break down the key components:

VRF Configuration (VPN-A)

The instance type is VRF, meaning this is an L3VPN (Layer 3 VPN).

The routing instance contains a static route (10.1.0.0/16 next-hop 10.1.0.1).

The interface ge-0/0/2.0 is assigned to the VRF.

Route Distinguisher (RD): 172.17.20.1:1

VRF-Export Policy: vpn-a-export

VRF-Target: target:65512:1 (This defines which routes will be imported into the VRF).

VRF Export Policy (vpn-a-export)

The vpn-a-export policy adds two BGP communities (route targets) to exported VPN routes:

community add vpn-a-target;

community add vpn-m-target;

accept;

The vpn-a-target community corresponds to target:65512:1.

The vpn-m-target community corresponds to target:65512:2.

Policy-Options (Community Definitions)

community vpn-a-target members target:65512:1;

community vpn-m-target members target:65512:2;

This confirms that routes exported from this VRF will have BOTH target:65512:1 and target:65512:2.

Evaluating the Answer Choices

✅ Option A: "VPN routes are exported with the target:65512:1 and target:65512:2 route targets."

The vpn-a-export policy explicitly adds both vpn-a-target (65512:1) and vpn-m-target (65512:2) to exported routes.

This is correct. ✅

❌ Option B: "You cannot use the vrf-target and vrf-export statements in the same VRF."

This is incorrect.

Juniper allows the use of both vrf-target and vrf-export in the same VRF:

vrf-target is used for importing routes.

vrf-export defines export policies (which can add additional route targets).

This is incorrect. ❌

❌ Option C: "VPN routes with the target:65512:1 and target:65512:2 route targets are imported."

The vrf-target target:65512:1; statement only controls importing routes.

The import policy does not include target:65512:2, so routes tagged with target:65512:2 alone would not be imported into this VRF.

This is incorrect. ❌

❌ Option D: "VPN routes are exported with only the target:65512:1 route target."

The export policy (vpn-a-export) clearly adds both 65512:1 and 65512:2.

This is incorrect. ❌

Final Answer:

✅ A. VPN routes are exported with the target:65512:1 and target:65512:2 route targets.

Verification from Juniper Documentation

Juniper MPLS L3VPN Configuration Guide confirms that vrf-target is used for importing, while vrf-export can be used for exporting multiple route targets.

Juniper Routing Policy Documentation states that export policies can add multiple BGP communities (route targets).

RFC 4364 (BGP/MPLS IP VPNs) defines the use of route targets for VPN route control.