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

Question: 361. Which Junos command displays routes learned specifically through BGP?

1. show route protocol ospf
   2. show bgp summary
   3. show route protocol bgp
   4. show route forwarding-table

Correct Answer: 3. show route protocol bgp

Explanation:

The show route protocol bgp command filters the Junos routing table to display routes whose protocol source is BGP. It is useful when verifying whether BGP-learned prefixes have been installed in the routing table. show bgp summary focuses on BGP peer sessions and their status, while show route protocol ospf filters for OSPF-learned routes. The forwarding-table command shows forwarding information rather than specifically identifying BGP as the protocol source. This command is therefore useful when troubleshooting BGP route installation.

Question: 362. Which OSPF LSA type is generated by a Designated Router to describe a broadcast multiaccess network?

1. Type 2 Network LSA
   2. Type 5 AS External LSA
   3. Type 3 Summary LSA
   4. Type 1 Router LSA

Correct Answer: 1. Type 2 Network LSA

Explanation:

A Type 2 Network LSA is originated by the OSPF Designated Router on broadcast and certain multiaccess network segments. It describes the routers attached to that network and helps represent the multiaccess segment within the OSPF link-state database. Type 1 Router LSAs describe individual routers, Type 3 Summary LSAs are originated by ABRs for inter-area information, and Type 5 AS External LSAs describe external routes redistributed into OSPF. The DR’s Type 2 LSA helps reduce the amount of topology information that must be represented individually between every router on a shared segment.

Question: 363. What is the primary purpose of the BGP Local Preference attribute?

1. To identify the BGP next-hop address
   2. To influence the preferred outbound path within an autonomous system
   3. To prevent all route advertisements
   4. To identify the autonomous systems traversed by a route

Correct Answer: 2. To influence the preferred outbound path within an autonomous system

Explanation:

BGP Local Preference is used within an autonomous system to influence which exit point should be preferred for outbound traffic. When eligible paths are compared, a higher Local Preference value is generally preferred. Network administrators can apply routing policy to assign different Local Preference values based on business or network-design requirements. The NEXT_HOP attribute identifies the next-hop address, AS_PATH records autonomous systems traversed, and BGP communities can control route propagation. Local Preference is therefore primarily an internal path-selection attribute.

Question: 364. Which IPv4 prefix represents the private address range from 172.16.0.0 through 172.31.255.255?

1. 192.168.0.0/16
   2. 10.0.0.0/8
   3. 172.0.0.0/8
   4. 172.16.0.0/12

Correct Answer: 4. 172.16.0.0/12

Explanation:

The RFC 1918 private IPv4 range from 172.16.0.0 through 172.31.255.255 is represented by the 172.16.0.0/12 prefix. This range is commonly used for private networks and is not globally routable on the public Internet. The other RFC 1918 ranges are 10.0.0.0/8 and 192.168.0.0/16. The broader 172.0.0.0/8 range is not entirely private. Recognizing the exact private prefixes is important when designing addressing plans and troubleshooting route advertisements.

Question: 365. Which Junos command provides a concise summary of interface administrative and operational states?

1. show interfaces terse
   2. show interfaces detail
   3. show route
   4. show chassis hardware

Correct Answer: 1. show interfaces terse

Explanation:

The show interfaces terse command provides a compact summary of interfaces, including their administrative and operational states. It is commonly used as a quick troubleshooting command to determine whether physical and logical interfaces are up or down. The regular show interfaces command provides much more detailed information, while show route displays routing information and show chassis hardware displays hardware inventory. Because it presents interface status in a concise format, show interfaces terse is particularly useful for an initial interface-state check.

Question: 366. Which OSPF packet carries LSAs from one router to another?

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

Correct Answer: 3. Link-State Update

Explanation:

OSPF Link-State Update (LSU) packets carry LSAs between OSPF routers. An LSU can contain one or more LSAs, including information needed to synchronize or update the link-state database. Hello packets discover and maintain neighbors, Database Description packets provide summaries of database contents, and Link-State Acknowledgment packets confirm receipt of LSAs. Understanding the different OSPF packet types is important when troubleshooting adjacency formation and link-state database synchronization.

Question: 367. Which BGP attribute provides the sequence of autonomous systems traversed by a route advertisement?

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

Correct Answer: 4. AS_PATH

Explanation:

The BGP AS_PATH attribute records the autonomous systems through which a route advertisement has passed. It is important for both path selection and loop prevention. When a BGP router detects its own autonomous system number in an incoming AS_PATH, it can reject the route to prevent a routing loop. AS_PATH length can also influence the best-path decision, with shorter paths generally preferred when the relevant earlier criteria are equal. NEXT_HOP identifies the forwarding next hop, while Local Preference and MED serve different path-selection purposes.

Question: 368. Which Junos command displays the current OSPF neighbor relationships?

1. show route protocol ospf
   2. show ospf neighbor
   3. show ospf database
   4. show bgp summary

Correct Answer: 2. show ospf neighbor

Explanation:

The show ospf neighbor command displays information about OSPF neighbors and their adjacency states. It can be used to verify whether expected neighbors have been discovered and whether their adjacencies have progressed to the appropriate state. show ospf database provides information about the OSPF link-state database, while show route protocol ospf shows routes learned through OSPF. show bgp summary is used for BGP peer sessions. Therefore, show ospf neighbor is the direct command for examining OSPF neighbor relationships.

Question: 369. Which IPv6 prefix identifies link-local unicast addresses?

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

Correct Answer: 3. FE80::/10

Explanation:

IPv6 link-local unicast addresses use the FE80::/10 prefix. They are intended for communication on the local network segment and are not routed beyond the local link. Link-local addresses are important for IPv6 functions such as Neighbor Discovery and can also be used by routing protocols. FF00::/8 is the multicast range, FC00::/7 is used for unique local addresses, and 2000::/3 is commonly used for global unicast addressing. Link-local addressing is therefore fundamental to normal IPv6 operation.

Question: 370. Which Junos command is used to validate a candidate configuration without activating it?

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

Correct Answer: 1. commit check

Explanation:

The commit check command validates the candidate configuration for syntax and configuration consistency without activating the changes. It is useful before a normal commit because it can identify configuration problems while leaving the active configuration unchanged. commit activates the candidate configuration, show | compare displays differences between candidate and active configurations, and rollback can load a previous configuration version. Therefore, commit check is specifically intended for pre-commit validation.

Question: 371. Which BGP community prevents a route from being advertised to any BGP peer?

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

Correct Answer: 4. no-advertise

Explanation:

The BGP no-advertise community tells a BGP speaker not to advertise the associated route to any BGP peer. It is therefore a strong route-propagation control mechanism. The no-export community has a narrower purpose: it prevents advertisement outside the local autonomous system or applicable confederation boundary. The internet community does not impose this restriction and generally permits advertisement according to policy. Understanding the distinction between no-advertise and no-export is important when controlling BGP route propagation.

Question: 372. Which OSPF state indicates that the neighboring routers have completed database synchronization?

1. Exchange
   2. Full
   3. Init
   4. 2-Way

Correct Answer: 2. Full

Explanation:

The OSPF Full state indicates that neighboring routers have completed the required database synchronization and have matching relevant link-state information for the adjacency. This is normally the desired final state for routers that need a full OSPF adjacency. The Exchange state involves exchanging Database Description information, while Init indicates that a Hello has been received but bidirectional communication has not yet been confirmed. The 2-Way state indicates bidirectional communication but does not necessarily mean that the routers have formed a full adjacency.

Question: 373. Which BGP attribute is generally preferred when its value is lower and can influence the selection of an entry point into an autonomous system?

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

Correct Answer: 1. MED

Explanation:

The Multi-Exit Discriminator (MED) is a BGP attribute that can influence how a neighboring autonomous system selects an entry point when multiple connections are available. Lower MED values are generally preferred when comparing applicable routes from the same neighboring AS. Local Preference generally favors higher values and is used primarily within an AS for outbound path selection. AS_PATH is considered differently during BGP path selection, while NEXT_HOP identifies the address used to reach the route. MED is therefore the attribute described by the lower-value preference.

Question: 374. Which Junos command displays the detailed attributes of a particular route?

1. show route protocol bgp
   2. show interfaces terse
   3. show route <prefix> detail
   4. show route forwarding-table

Correct Answer: 3. show route <prefix> detail

Explanation:

The show route <prefix> detail command provides detailed information about a specified route. The output can include protocol information, route preference, next-hop details, routing-table information, and other attributes associated with the route. It is especially useful when investigating why a route was selected or how the device plans to forward traffic toward a destination. The other commands provide broader filtered route information, interface status, or forwarding-table information rather than detailed information about one specified route.

Question: 375. Which protocol is commonly used as an interior gateway protocol based on the link-state routing model and supports hierarchical areas?

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

Correct Answer: 3. OSPF

Explanation:

OSPF is a link-state interior gateway protocol that supports hierarchical routing through multiple areas. Area 0 is the backbone area, and other OSPF areas can connect to it through Area Border Routers. This hierarchical design helps control the scope of link-state information and supports larger network deployments. RIP is a distance-vector protocol, BGP is primarily an exterior gateway protocol, and ARP is an address-resolution protocol rather than a routing protocol. OSPF therefore matches the described characteristics.

Question: 376. Which Junos command displays active system alarms?

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

Correct Answer: 4. show system alarms

Explanation:

The show system alarms command displays alarms currently reported by the Junos device. These alarms can provide important information about hardware, environmental, or other system conditions that may require attention. show system uptime provides runtime information, show chassis hardware shows installed hardware, and show route displays routing information. When troubleshooting a device for active system-level problems, checking show system alarms is a useful diagnostic step.

Question: 377. Which OSPF area is normally used as the backbone for inter-area routing?

1. Area 1
   2. Area 0
   3. Area 10
   4. Area 100

Correct Answer: 2. Area 0

Explanation:

OSPF Area 0 is the backbone area and provides the central structure for inter-area routing. Other OSPF areas normally connect to the backbone through Area Border Routers. Maintaining proper connectivity to Area 0 is important for exchanging routing information between different OSPF areas. Although additional areas can use many different numerical identifiers, Area 0 has the specific backbone role defined by OSPF. This hierarchical design helps limit the scope of link-state information and supports scalable routing.

Question: 378. Which mechanism allows multiple physical Ethernet interfaces to operate together as a single logical link?

1. LACP
   2. VRRP
   3. BFD
   4. GRES

Correct Answer: 1. LACP

Explanation:

LACP, or Link Aggregation Control Protocol, is used to negotiate and maintain link aggregation between compatible devices. Multiple physical Ethernet interfaces can participate in a logical aggregated Ethernet interface, providing increased capacity and link redundancy. VRRP provides first-hop gateway redundancy, BFD provides rapid failure detection, and GRES supports Routing Engine switchover. LACP is therefore the technology associated with combining multiple physical Ethernet links into one logical connection.

Question: 379. Which Junos routing table is used for IPv4 unicast routes?

1. inet6.0
   2. iso.0
   3. inet.0
   4. mpls.0

Correct Answer: 3. inet.0

Explanation:

The Junos inet.0 routing table is the primary routing table for IPv4 unicast routes. IPv6 unicast routes are normally stored in inet6.0. Other routing tables, such as mpls.0, serve different protocol or forwarding purposes. Knowing which routing table contains a route is useful when troubleshooting route installation, routing instances, and forwarding behavior. For a standard IPv4 unicast route in the main routing instance, inet.0 is the expected routing table.

Question: 380. Which BGP attribute identifies the IP address used as the next hop toward an advertised destination?

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

Correct Answer: 4. NEXT_HOP

Explanation:

The BGP NEXT_HOP attribute identifies the IP address that a router should use as the next hop when forwarding traffic toward the advertised destination. The receiving router must be able to resolve that next-hop address through its routing information for the BGP route to be usable. AS_PATH records autonomous systems traversed, Local Preference influences outbound path selection within an AS, and Origin describes how the route entered BGP. NEXT_HOP is therefore the attribute directly associated with identifying the forwarding next hop.