A service provider is troubleshooting a route that is missing from the routing table on a core router. The router's IS-IS database shows an LSP from the origin router with a sequence number of 0x0000000A and a remaining lifetime of 0. What is the most likely reason the route is not being used?

The LSP has been purged and is being flooded as a zero-age LSP to remove it from all databases.

The LSP has a sequence number that is too low and is being ignored by the receiving router.

The LSP is still valid but the router is waiting for a CSNP to confirm the database is synchronized.

The LSP is being held in the database but is not used for SPF because the overload bit is set.

How are LSPs flooded throughout an IS-IS area?

Only to the designated router, which then redistributes them.

To all adjacent neighbors except the one from which the LSP was received.

Only to routers within the same area, not to Level 2 routers.

Using a spanning tree to avoid loops.

A network engineer is troubleshooting a routing issue in an IS-IS area. The engineer notices that a router is receiving an LSP with a sequence number that is lower than the one in its database. The router also receives a PSNP from the neighbor that sent the LSP. What should the router do?

Send its newer LSP to the neighbor to correct the neighbor's database.

Purge the LSP from its database and request a new one.

Replace its LSP with the lower sequence number LSP.

What is the purpose of a Complete Sequence Number PDU (CSNP) in IS-IS?

To acknowledge receipt of an LSP.

To request a specific LSP from a neighbor.

To advertise the complete list of LSPs in the router's link-state database.

To establish adjacency between two routers.

An IS-IS router receives an LSP with a sequence number that is higher than the one currently in its database. What action should the router take?

Install the new LSP in the database, mark it for flooding, and send a PSNP to acknowledge receipt.

Ignore the LSP because the sequence number is not the expected next value.

Send a CSNP to request the full database from the sender.

Replace the old LSP and immediately purge it from the database.

Juniper NetworksCertified Specialist, Service Provider Routing and Switching (JNCIS-SP)

Domain 3Objective 1

Link-State Database JN0-364 Practice Questions (Page 4)

Part of the Intermediate System to Intermediate System (IS-IS) domain, which makes up ~12% of our current practice bank. Juniper Networks does not publish an official question count, but from its 90-minute exam (~35–60 total, ~4–7 in this domain), expect 1–1 from this objective — we provide 22 practice questions to prepare you well beyond it. (estimate)

22questions here

5free pages

6concepts

Questions 16–20

16application · medium
A service provider is troubleshooting a route that is missing from the routing table on a core router. The router's IS-IS database shows an LSP from the origin router with a sequence number of 0x0000000A and a remaining lifetime of 0. What is the most likely reason the route is not being used?
Select an answer first
17foundation · easy
How are LSPs flooded throughout an IS-IS area?
Select an answer first
18expert · hard
A network engineer is troubleshooting a routing issue in an IS-IS area. The engineer notices that a router is receiving an LSP with a sequence number that is lower than the one in its database. The router also receives a PSNP from the neighbor that sent the LSP. What should the router do?
Select an answer first
19foundation · easy
What is the purpose of a Complete Sequence Number PDU (CSNP) in IS-IS?
Select an answer first
20application · medium
An IS-IS router receives an LSP with a sequence number that is higher than the one currently in its database. What action should the router take?
Select an answer first

Finished these 5 questions?

Review the revealed explanations, or continue through the curriculum.

Next 5 questions →Back to JN0-364

Free Basic Practice is a study aid with revealable answers — not a scored exam. Examers.io is independent and not affiliated with or endorsed by Juniper Networks. “JN0-364” is a trademark of its owner, used for identification only.