View Full Juniper JN0-364  Exam Dumps and Practice Test Dumps

Question: 341. Which Junos command displays detailed information about the installed routing table?

1. show interfaces
   2. show route
   3. show chassis hardware
   4. show system alarms

Correct Answer: 2. show route

Explanation:

The show route command displays the Junos routing table and provides information about routes known to the routing system. The output can include destination prefixes, route preferences, protocol sources, next hops, and route states. Additional options can be used to filter or obtain more detailed information about specific routes. show interfaces focuses on interface information, show chassis hardware displays hardware inventory, and show system alarms reports active system alarms. Therefore, show route is the fundamental command for examining the routing table.

Question: 342. Which BGP attribute is primarily used to identify how a route entered the BGP system?

1. Origin
   2. MED
   3. NEXT_HOP
   4. Local Preference

Correct Answer: 1. Origin

Explanation:

The BGP Origin attribute indicates how a route was introduced into BGP. Common Origin values include IGP, EGP, and Incomplete, with IGP generally being preferred over EGP and Incomplete during the relevant stage of BGP path selection. NEXT_HOP identifies the next-hop address, Local Preference influences outbound path selection within an autonomous system, and MED can influence how a neighboring AS selects an entry point. Understanding the Origin attribute helps explain why one otherwise eligible BGP path may be selected over another.

Question: 343. Which protocol is used by OSPF routers to discover neighbors and maintain their relationships?

1. Database Description
   2. Link-State Request
   3. Hello
   4. Link-State Acknowledgment

Correct Answer: 3. Hello

Explanation:

OSPF Hello packets are used to discover neighboring routers and maintain OSPF neighbor relationships. Hello packets are sent periodically through OSPF-enabled interfaces and contain parameters that must be compatible for an adjacency to form. They also allow routers to confirm that neighboring routers remain reachable. Database Description packets are used during database synchronization, Link-State Requests request specific LSAs, and Link-State Acknowledgments confirm receipt of LSAs. Therefore, Hello is the primary OSPF packet type associated with neighbor discovery and maintenance.

Question: 344. Which IPv6 prefix represents the unique local unicast address space?

1. FE80::/10
   2. FF00::/8
   3. 2000::/3
   4. FC00::/7

Correct Answer: 4. FC00::/7

Explanation:

The IPv6 FC00::/7 prefix is designated for Unique Local Addresses (ULAs). These addresses are intended for private addressing within organizations and are not designed for global Internet routing. The range includes the commonly used FD00::/8 portion for locally assigned ULA prefixes. FE80::/10 is the link-local range, FF00::/8 is multicast, and 2000::/3 is the commonly used global unicast range. ULAs can therefore provide private IPv6 addressing without relying on globally routable prefixes.

Question: 345. Which Junos command displays the differences between the candidate configuration and the active configuration?

1. show | compare
   2. show configuration
   3. commit check
   4. rollback

Correct Answer: 1. show | compare

Explanation:

The Junos show | compare command is used in configuration mode to display differences between the candidate configuration and the currently active configuration. It is particularly useful before committing changes because it allows an administrator to review exactly what will be changed. show configuration displays the configuration itself, while commit check validates the candidate configuration without activating it. The rollback command is used to load an earlier configuration version into the candidate configuration.

Question: 346. What is the main purpose of an OSPF Backup Designated Router?

1. To replace BGP as the external routing protocol
   2. To maintain a backup role so it can become the DR if the current DR fails
   3. To calculate SPF routes for all OSPF areas
   4. To assign IP addresses to OSPF interfaces

Correct Answer: 2. To maintain a backup role so it can become the DR if the current DR fails

Explanation:

The OSPF Backup Designated Router (BDR) provides redundancy for the Designated Router on broadcast and certain multiaccess network types. The BDR maintains the necessary relationships so that it can take over the DR role if the current DR becomes unavailable. This helps avoid the need for a completely new election and reduces disruption to OSPF operations. The BDR does not calculate all routing paths independently of OSPF SPF processing, assign IP addresses, or replace BGP.

Question: 347. Which Junos routing instance type can provide a separate virtual routing environment on the same physical device?

1. Virtual Router
   2. Bridge
   3. Forwarding
   4. Ethernet-switching

Correct Answer: 1. Virtual Router

Explanation:

A Virtual Router routing instance provides a separate routing environment on a Junos device. Interfaces and routes associated with the instance can be isolated from the main routing table and from other routing instances. This can be useful when logically separating networks on the same physical platform. Routing instances have different types and purposes, so understanding their behavior is important when designing or troubleshooting virtualized routing environments. A Virtual Router instance is specifically associated with maintaining an independent routing table and routing context.

Question: 348. Which BGP attribute is commonly used to influence the preferred inbound path into an autonomous system from a neighboring AS?

1. Local Preference
   2. Origin
   3. MED
   4. AS_PATH

Correct Answer: 3. MED

Explanation:

The Multi-Exit Discriminator (MED) can be used to communicate a preference for one entry point into an autonomous system when multiple links exist between neighboring autonomous systems. A lower MED is generally preferred when comparing otherwise eligible paths from the same neighboring AS. Local Preference is primarily used internally to influence outbound path selection, while AS_PATH records the autonomous systems traversed by a route. Origin indicates how a route was introduced into BGP. MED therefore provides a mechanism for influencing certain inbound traffic decisions by a neighboring AS.

Question: 349. Which OSPF state indicates that a router has received a Hello packet from a neighbor but has not yet established bidirectional communication?

1. Full
   2. Init
   3. Exchange
   4. Loading

Correct Answer: 2. Init

Explanation:

The OSPF Init state occurs when a router receives a Hello packet from a neighboring router but does not yet see its own router ID listed in the neighbor’s Hello. This means the receiving router has heard from the neighbor, but bidirectional communication has not yet been confirmed. Once the routers see each other in their Hello packets, the relationship can progress to 2-Way. Full indicates synchronized link-state databases, while Exchange and Loading occur during later stages of adjacency formation and database synchronization.

Question: 350. Which protocol uses a link-state database and the Shortest Path First algorithm to calculate routes?

1. RIP
   2. BGP
   3. OSPF
   4. ARP

Correct Answer: 3. OSPF

Explanation:

OSPF is a link-state routing protocol that maintains a link-state database representing the topology of an OSPF area. It uses the Shortest Path First algorithm, based on Dijkstra’s algorithm, to calculate the shortest paths through that topology. RIP uses a distance-vector approach and primarily uses hop count, while BGP uses path attributes for inter-AS route selection. ARP is not a routing protocol at all; it resolves IPv4 addresses to Layer 2 MAC addresses on local networks.

Question: 351. Which Junos command provides hardware inventory information for the router or switch?

1. show system uptime
   2. show route
   3. show chassis hardware
   4. show interfaces terse

Correct Answer: 3. show chassis hardware

Explanation:

The show chassis hardware command displays hardware inventory information for the Junos device. Depending on the platform, the output can include chassis components, Routing Engines, line cards, modules, and other hardware details. This command is useful when verifying installed hardware or troubleshooting hardware-related issues. show system uptime provides system runtime information, show route displays routing information, and show interfaces terse provides a concise interface status summary.

Question: 352. Which BGP mechanism allows a router to use multiple eligible paths to the same destination when the paths satisfy the required multipath conditions?

1. Route reflection
   2. BGP multipath
   3. MED
   4. AS_PATH prepending

Correct Answer: 2. BGP multipath

Explanation:

BGP multipath allows multiple eligible BGP paths to the same destination to be installed and used when the configured multipath requirements are satisfied. This can provide load sharing and additional path redundancy. Normally, BGP selects a single best path, but multipath functionality can allow several equivalent or suitably comparable paths to participate in forwarding. Route reflection addresses iBGP scalability, MED influences certain path-selection decisions, and AS_PATH prepending is commonly used to influence path selection rather than to enable multipath forwarding.

Question: 353. Which IPv6 address range is used for multicast addresses?

1. FE80::/10
   2. FC00::/7
   3. FF00::/8
   4. 2000::/3

Correct Answer: 3. FF00::/8

Explanation:

IPv6 multicast addresses use the FF00::/8 prefix. Multicast allows a packet to be delivered to a group of interested receivers rather than to a single destination. IPv6 relies heavily on multicast for functions such as Neighbor Discovery. FE80::/10 is reserved for link-local unicast addresses, FC00::/7 is used for unique local addressing, and 2000::/3 represents the commonly used global unicast range. Recognizing IPv6 address types is important when interpreting routing and neighbor-discovery traffic.

Question: 354. Which OSPF packet is used to exchange summaries of the link-state database between neighbors?

1. Link-State Update
   2. Database Description
   3. Hello
   4. Link-State Request

Correct Answer: 2. Database Description

Explanation:

OSPF Database Description (DBD) packets are used during adjacency formation to exchange summaries of the LSAs contained in each router’s link-state database. The summaries allow routers to determine which LSAs they need to request. Link-State Request packets then request specific missing or newer LSAs, while Link-State Update packets carry the actual LSAs. Hello packets are used for neighbor discovery and maintenance. Database Description packets are therefore an important part of OSPF database synchronization.

Question: 355. Which BGP attribute is used to identify the IP address that should be used as the next hop toward a destination?

1. NEXT_HOP
   2. Origin
   3. MED
   4. Local Preference

Correct Answer: 1. NEXT_HOP

Explanation:

The BGP NEXT_HOP attribute identifies the IP address that should be used as the next hop for reaching a destination prefix. The receiving router must be able to resolve that next-hop address through its routing information for the BGP route to be usable. Local Preference influences the preferred outbound path inside an autonomous system, MED can influence certain inbound path decisions, and Origin identifies how the route entered BGP. Correct next-hop resolution is therefore essential to BGP route installation and forwarding.

Question: 356. Which Junos command displays the current system uptime and related system status information?

1. show system alarms
   2. show chassis hardware
   3. show system uptime
   4. show route

Correct Answer: 3. show system uptime

Explanation:

The show system uptime command displays information about how long the Junos device has been running along with related system uptime information. It is useful when determining whether a device has recently rebooted or when reviewing system runtime during troubleshooting. show system alarms focuses on active alarms, show chassis hardware displays hardware inventory, and show route displays routing information. The uptime command is therefore the appropriate choice when investigating system runtime and recent reboot behavior.

Question: 357. What is the main function of an OSPF Area Border Router?

1. To connect different OSPF areas and exchange inter-area routing information
   2. To provide Layer 2 link aggregation
   3. To establish BGP TCP sessions
   4. To replace the OSPF DR on every network

Correct Answer: 1. To connect different OSPF areas and exchange inter-area routing information

Explanation:

An Area Border Router (ABR) connects two or more OSPF areas and maintains OSPF information for its attached areas. It can advertise routing information between areas using inter-area LSAs, such as Type 3 Summary LSAs. ABRs are important to OSPF’s hierarchical design because they help control the scope of link-state information and support route summarization between areas. An ABR is not responsible for Ethernet link aggregation or BGP session establishment, and it does not replace the DR on every OSPF network.

Question: 358. Which BGP community generally indicates that a route should be advertised to BGP peers, subject to routing policy?

1. no-export
   2. no-advertise
   3. internet
   4. local-AS

Correct Answer: 3. internet

Explanation:

The BGP internet community indicates that the route can be advertised to other BGP peers, subject to the policies configured on the participating routers. It is essentially the broad advertisement community and does not impose the propagation restrictions associated with communities such as no-export or no-advertise. no-export restricts advertisement outside the local autonomous system, while no-advertise prevents advertisement to BGP peers. Understanding well-known BGP communities helps administrators control route propagation across different parts of a network.

Question: 359. Which Junos command can be used to verify the hardware components installed in a device?

1. show route
   2. show chassis hardware
   3. show bgp summary
   4. show ospf neighbor

Correct Answer: 2. show chassis hardware

Explanation:

The show chassis hardware command provides an inventory of hardware components installed in the Junos device. It can show information about chassis components, modules, Routing Engines, line cards, and other platform-specific hardware. This makes it useful when verifying hardware installation or troubleshooting hardware configuration. show route examines routing information, show bgp summary displays BGP session information, and show ospf neighbor displays OSPF neighbor relationships. Hardware inventory is therefore best checked with the chassis hardware command.

Question: 360. Which BGP path attribute is generally preferred when it has a higher value and is used to influence outbound traffic within an autonomous system?

1. MED
   2. AS_PATH
   3. Local Preference
   4. Origin

Correct Answer: 3. Local Preference

Explanation:

Local Preference is a BGP attribute used within an autonomous system to influence the preferred exit point for outbound traffic. A higher Local Preference value is generally preferred during BGP path selection. Network administrators can apply routing policy to assign different values based on factors such as the source of a route or desired traffic-engineering behavior. MED is generally preferred at a lower value when applicable, AS_PATH length is considered differently, and Origin represents how a route entered BGP. Local Preference is therefore the attribute described by this behavior.