Courseiva

JNCIP-ENT · domain

BGP Advanced

This domain covers advanced BGP on Junos: route reflection, next-hop resolution and tracking, multipath and load balancing, attribute manipulation with routing policy, and scaling behaviors. Questions are scenario-based, asking you to pick the right Junos command, policy evaluation point, or configuration statement to diagnose and fix a specific BGP behavior.

37 questions9 easy16 medium12 hard

Focused practice

Practice BGP Advanced questions

Scored sessions drawing only from this domain — pick a length below.

Start 20-question practice test →

What this domain covers

What to know about BGP Advanced

Be able to diagnose why a BGP route is not installed or not load-balanced, and know where Junos evaluates BGP policy. The most important thing is getting next-hop resolution and multipath eligibility conditions right before changing policy.

Next-hop resolution and tracking using show route detail and the resolve command in Junos

Outbound routing policy evaluation order for as-path prepend and community matching

Route reflector cluster design, client peering, and loop prevention with cluster IDs and originator IDs

BGP multipath eligibility, including as-path, MED, and next-hop requirements under routing-options

Watch out for

Common BGP Advanced exam traps

  • ▸Assuming a BGP route with an unresolved next hop is hidden, when it may be present but not installed in the forwarding table
  • ▸Applying outbound policy before route selection or export, instead of at the correct export or neighbor evaluation point
  • ▸Enabling multipath without matching as-path, origin, MED, or next-hop conditions, so only one path is used

Question index

All BGP Advanced questions (37)

Click any question to see the full explanation, or start a practice session above.

1

Which TWO BGP attributes are classified as well-known mandatory attributes that must be recognized by all BGP implementations? (Choose TWO)

Easy
2

An engineer needs to ensure that a Junos router balances BGP traffic across multiple paths with unequal IGP costs. Which feature must be configured to achieve this?

Easy
3

Which command allows an administrator to view the active BGP routes along with their associated communities on a Junos device?

Easy
4

An enterprise network uses a BGP route reflector (RR) architecture where client routers reflect routes to each other. A non-client router sends a route with an Originator ID and Cluster List to the RR. How does the route reflector handle these attributes when reflecting the route to other clients?

Hard
5

During BGP route resolution on Junos, an indirect next hop is encountered. What mechanism does Junos use to resolve this indirect next hop to a direct forwarding next hop?

Hard
6

You are configuring a BGP Route Reflector (RR) in a Junos environment. To prevent routing loops within the iBGP cluster, what mechanism does the route reflector use to track the path of reflected routes?

Medium
7

You are the network architect for a service provider that offers BGP/MPLS IP VPNs to enterprise customers. A customer reports that routes from one of its sites are being leaked into the global Internet table of a remote provider edge (PE) router. You have already verified that the VRF import policy on the remote PE is correct and that the route target (RT) communities are properly assigned. Which Junos configuration on the originating PE router is the most likely cause of the route leak?

Medium
8

Which THREE actions occur during the BGP next-hop resolution process on a Junos device when evaluating an eBGP-learned route? (Choose THREE)

Hard
9

An enterprise network uses BGP route reflection. The design team has deployed two route reflectors in the same cluster for redundancy, with all client routers peering to both route reflectors. After a link failure, some clients receive duplicate route advertisements. Which BGP attribute is used to prevent routing loops within a route reflection cluster, and how does it function?

Medium
10

Which Junos configuration hierarchy is used to define a BGP peer group to simplify neighbor configurations?

Easy
11

An engineer is troubleshooting a BGP route reflection topology where a non-client IBGP peer sends a route to a route reflector. Will the route reflector reflect this route to other non-client IBGP peers?

Medium
12

You want to tag specific BGP routes with a community value using a Junos policy framework. Which configuration snippet correctly defines a community named 'CUSTOM-COMM' with value 65000:100?

Easy
13

When designing a BGP confederation architecture, which TWO rules govern how sub-AS numbers and attributes behave across confederation boundaries? (Choose two)

Hard
14

Which TWO actions can be performed using Junos BGP routing policies? (Choose two)

Easy
15

An operator configures a BGP routing policy to modify the Local Preference attribute. Under which BGP neighbor relationship type can Local Preference be advertised and evaluated?

Easy
16

An administrator is configuring BGP multipath on a Junos router. The router has two BGP paths to the same destination: one with a MED of 100 and another with a MED of 200. Both paths are from the same neighboring AS. The administrator wants both paths to be installed in the forwarding table for load balancing. Which configuration is required?

Medium
17

Which BGP attribute is used to prevent routing loops in a BGP confederation?

Easy
18

An engineer notices that a Junos device is not installing a BGP route into the forwarding table because the BGP next hop is unresolved. Which tool or command can be used to troubleshoot how the BGP next hop is being resolved in the Junos routing table?

Medium
19

An administrator applies a policy containing 'as-path-prepend "65001 65001"' to outbound BGP updates sent to an external provider. What is the primary objective of this configuration?

Medium
20

When configuring a BGP confederation, how are external peers outside the confederation affected by the internal sub-AS structure?

Medium
21

A Junos router receives a BGP route containing multiple extended and large communities. The administrator writes a routing policy to filter routes based on large communities. Which format is used to define a large community in Junos policy-options?

Hard
22

Which BGP community is a well-known transitive community used to prevent a route from being advertised outside of a local autonomous system?

Easy
23

An administrator implements BGP entropy labels and path load balancing on a Junos routing platform. During packet forwarding for a BGP-learned IPv4 prefix with multiple equal-cost paths, how does Junos determine the output interface when hash-based load balancing is active?

Hard
24

In a BGP confederation setup, two member ASNs (65001 and 65002) belong to a larger confederation AS (65100). When routes are advertised between these two member ASs, how is the AS path attribute handled?

Hard
25

You are the network architect for a large enterprise that uses BGP route reflectors (RRs) in a single cluster. You want to ensure that when an RR receives a route from a client, it reflects that route to other clients but does not reflect it back to the originating client. Which BGP attribute or mechanism prevents the route from being reflected back to the originating client?

Medium
26

An engineer needs to ensure that routes received from an external BGP peer are evaluated using multipath load balancing across different next hops. By default, Junos requires several conditions to be met for multipath. Which condition is mandatory for BGP multipath to consider two paths as valid candidates?

Medium
27

An operator configures BGP attribute value manipulation using a Junos routing policy. Specifically, the policy uses 'as-path-action prepend' combined with community matching. When is this outbound policy evaluated relative to BGP route selection?

Hard
28

An engineer is configuring BGP route resolution and next-hop tracking in Junos. Which TWO circumstances will cause a BGP next hop to be marked as unresolved or unusable? (Choose two)

Hard
29

When configuring a BGP route reflector cluster in Junos, which THREE guidelines or operational behaviors should an engineer keep in mind? (Choose THREE)

Medium
30

A Junos router is configured with BGP path selection, and multiple paths arrive with different MED values. Under what specific condition does Junos compare the MED values of paths from different autonomous systems during route selection?

Hard
31

An enterprise runs a Junos BGP routing domain where a route reflector (RR) in cluster 10.0.0.1 reflects an eBGP-learned route to its iBGP clients. A client router receives the reflected route and notices the ORIGINATOR_ID attribute is set to 10.0.0.1, while the CLUSTER_LIST attribute contains 10.0.0.1. The client also has a second route reflector in the same cluster (10.0.0.2) as a peer. When the client advertises this route to the second route reflector, what does the second route reflector do with the update?

Hard
32

A network engineer has configured BGP multipath on a Junos routing device using the 'multipath' statement under the routing-options bgp hierarchy. However, traffic is still only utilizing a single path. Which condition must be met for BGP multipath to become active for a destination prefix?

Medium
33

A network administrator wants to advertise an aggregate BGP route while suppressing the more specific component routes from being sent to external peers. Which Junos routing-options configuration achieves this?

Medium
34

You are troubleshooting a Junos router that is not selecting the expected BGP path for a prefix. The router receives the prefix from two eBGP peers. Peer A sends the route with a MED of 50 and an AS path length of 3. Peer B sends the same prefix with a MED of 100 and an AS path length of 2. Both peers are in the same neighboring AS. The router is configured with 'multipath multiple-as' and 'bgp multipath' under the global BGP hierarchy. Which path will be selected as best, and why?

Hard
35

Which THREE parameters are part of the standard Junos BGP route selection algorithm prior to evaluating the router ID? (Choose three)

Medium
36

A network designer needs to implement BGP route reflection where multiple route reflectors are deployed in the same cluster to provide redundancy. What parameter must be identical across all route reflectors in that same cluster to prevent routing loops?

Medium
37

An administrator configures BGP dampening on a Junos router to mitigate the impact of flapping routes. When a route exceeds the reuse threshold after being suppressed, what happens to its penalty value?

Medium

Frequently asked questions

What does the BGP Advanced domain cover on the JNCIP-ENT exam?
Be able to diagnose why a BGP route is not installed or not load-balanced, and know where Junos evaluates BGP policy. The most important thing is getting next-hop resolution and multipath eligibility conditions right before changing policy.
How many questions are in this domain?
This page lists all 37 BGP Advanced questions in the JNCIP-ENT question bank. The actual exam draws from this domain proportionally to its weighting in the official exam blueprint.
What is the best way to practise this domain?
Start with a short focused session (10 questions) to identify gaps, then work through explanations. Repeat with a longer session once the weak areas feel solid.
Can I practise only BGP Advanced questions?
Yes — the session launcher on this page filters questions to this domain only. Choose any session length for inline explanations and scoring.
Juniper Networks Enterprise Routing and Switching, Professional (JNCIP-ENT, JN0-650) (JNCIP-ENT) BGP Advanced Practice Questions