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

 

Question: 381. Which Junos command displays the routing table entries learned from OSPF?

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

Correct Answer: 2. show route protocol ospf

Explanation:

The show route protocol ospf command filters the Junos routing table to display routes learned through OSPF. It is useful when verifying whether OSPF has successfully installed routes into the routing table. show ospf database displays the OSPF link-state database rather than only installed routes, while show ospf neighbor focuses on OSPF adjacencies. show route protocol bgp specifically filters for BGP routes. This distinction is useful when determining whether an OSPF route has progressed from the protocol database into the active routing table.

Question: 382. Which BGP attribute is used within an autonomous system to select a preferred exit point for outbound traffic?

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

Correct Answer: 4. Local Preference

Explanation:

BGP Local Preference is an internal autonomous-system attribute used to influence the preferred exit point for outbound traffic. A higher Local Preference value is generally preferred when comparing otherwise eligible BGP paths. Administrators can use routing policy to assign different values to routes received through different external connections. MED serves a different purpose by influencing certain inbound path decisions, AS_PATH records autonomous systems traversed by the route, and NEXT_HOP identifies the next-hop address. Local Preference is therefore the primary attribute described by this requirement.

Question: 383. Which OSPF packet is periodically transmitted to discover and maintain neighboring routers?

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

Correct Answer: 1. Hello

Explanation:

OSPF Hello packets are periodically transmitted through OSPF-enabled interfaces to discover neighbors and maintain existing neighbor relationships. They contain information such as the router ID, area information, timers, and other parameters needed to establish compatible OSPF adjacencies. Database Description packets are used to exchange summaries of link-state databases, Link-State Requests request specific LSAs, and Link-State Updates carry LSAs. Therefore, Hello packets are the fundamental mechanism for OSPF neighbor discovery and relationship maintenance.

Question: 384. Which IPv4 prefix represents the default route?

1. 127.0.0.0/8
   2. 255.255.255.255/32
   3. 0.0.0.0/0
   4. 224.0.0.0/4

Correct Answer: 3. 0.0.0.0/0

Explanation:

The IPv4 default route is represented by 0.0.0.0/0. Because it has a prefix length of zero, it can match any IPv4 destination for which no more specific route exists. Routers commonly use a default route to forward traffic toward an upstream gateway or provider when a destination is not otherwise present in the routing table. 127.0.0.0/8 is reserved for loopback, 255.255.255.255/32 is the limited broadcast address, and 224.0.0.0/4 is the IPv4 multicast range.

Question: 385. Which Junos high-availability feature helps maintain packet forwarding during a Routing Engine switchover?

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

Correct Answer: 2. GRES

Explanation:

Graceful Routing Engine Switchover (GRES) is a Junos high-availability feature designed to help preserve packet forwarding while control-plane responsibility transitions between Routing Engines. During a switchover, the Packet Forwarding Engine can continue forwarding traffic, helping minimize disruption. GRES should be distinguished from Nonstop Active Routing, which addresses preservation of routing-protocol state, and from BFD, LACP, and VRRP, which provide failure detection, link aggregation, and gateway redundancy respectively. GRES is specifically associated with Routing Engine switchover behavior.

Question: 386. Which OSPF LSA describes the links and networks associated with an individual router within an area?

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

Correct Answer: 4. Type 1 Router LSA

Explanation:

A Type 1 Router LSA is originated by an OSPF router to describe its links, interfaces, and directly connected networks within an area. These LSAs form an important part of the link-state database used by OSPF’s SPF calculation. Type 2 Network LSAs describe multiaccess networks and are originated by the DR, Type 3 Summary LSAs are used by ABRs to advertise inter-area networks, and Type 5 AS External LSAs describe external routes redistributed into OSPF. Therefore, Type 1 is the LSA associated with an individual router’s local topology.

Question: 387. Which BGP attribute can influence how a neighboring autonomous system selects an entry point into the local autonomous system?

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

Correct Answer: 2. MED

Explanation:

The Multi-Exit Discriminator (MED) can provide a neighboring autonomous system with information about which entry point into the local autonomous system is preferred when multiple interconnections exist. Lower MED values are generally preferred when comparing applicable routes from the same neighboring AS. Local Preference primarily influences outbound path selection within the local AS. Origin indicates how a route entered BGP, while NEXT_HOP identifies the address used to reach the route. MED is therefore the BGP attribute commonly associated with influencing inbound traffic through multiple connections.

Question: 388. Which Junos command displays detailed information about a specified route?

1. show route <prefix> detail
   2. show route terse
   3. show interfaces terse
   4. show bgp summary

Correct Answer: 1. show route <prefix> detail

Explanation:

The show route <prefix> detail command provides detailed information about a specific route in the Junos routing table. Depending on the route, the output can show the protocol source, route preference, next-hop information, routing-table details, and other attributes. This makes it useful when troubleshooting why a particular route was selected or how the router intends to forward traffic. show route terse provides a more compact view, while the interface and BGP commands focus on different operational information.

Question: 389. Which routing protocol uses link-state information and the SPF algorithm to calculate paths?

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

Correct Answer: 3. OSPF

Explanation:

OSPF is a link-state interior gateway protocol that builds a link-state database and uses the Shortest Path First algorithm to calculate routes. Each router maintains a representation of the topology within its OSPF area and calculates paths based on the available link-state information and configured costs. RIP uses a distance-vector approach, BGP uses path attributes for inter-AS route selection, and ARP is an address-resolution protocol. OSPF is therefore the protocol that directly matches both the link-state and SPF characteristics described.

Question: 390. Which Junos command displays the currently active configuration while in configuration mode?

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

Correct Answer: 2. show configuration

Explanation:

The show configuration command displays the configuration hierarchy while working in Junos configuration mode. It allows an administrator to inspect configured statements and settings. show | compare is used to compare the candidate configuration with the active configuration, while commit check validates the candidate configuration without activating it. show route is an operational-mode command for examining routing information. Therefore, show configuration is the appropriate command for viewing the current configuration hierarchy in configuration mode.

Question: 391. Which BGP community prevents a route from being advertised to any BGP peer?

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

Correct Answer: 3. no-advertise

Explanation:

The no-advertise BGP community instructs a BGP speaker not to advertise the associated route to any BGP peer. This provides strong control over route propagation. The no-export community is less restrictive because it prevents the route from being advertised outside the local autonomous system or applicable confederation boundary. The internet community does not impose a propagation restriction, while local-AS is associated with a different BGP policy function. Understanding these communities is important when controlling the distribution of selected prefixes.

Question: 392. Which IPv6 prefix is reserved for link-local unicast addressing?

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

Correct Answer: 1. FE80::/10

Explanation:

The FE80::/10 prefix identifies IPv6 link-local unicast addresses. These addresses are used for communication on the local network segment and are not intended to be routed beyond that link. IPv6 Neighbor Discovery makes extensive use of link-local addressing, and many IPv6 routing protocols also use link-local addresses for their local peer relationships. FF00::/8 is the multicast range, FC00::/7 is used for unique local addresses, and 2000::/3 represents the commonly used global unicast range.

Question: 393. Which Junos command displays OSPF neighbor adjacency information?

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

Correct Answer: 3. show ospf neighbor

Explanation:

The show ospf neighbor command displays OSPF neighbor relationships and their current adjacency states. It can be used to verify whether expected neighbors have been discovered and whether adjacencies have reached states such as 2-Way or Full. show ospf database displays the link-state database, while show route protocol ospf shows routes learned through OSPF. show bgp summary is used for BGP sessions. When troubleshooting OSPF adjacency formation, show ospf neighbor is therefore one of the most direct commands to use.

Question: 394. Which BGP attribute identifies the IP address that should be used as the next hop toward a destination?

1. MED
   2. AS_PATH
   3. NEXT_HOP
   4. Origin

Correct Answer: 3. NEXT_HOP

Explanation:

The BGP NEXT_HOP attribute identifies the IP address that should be used as the next hop when forwarding traffic toward the advertised destination. For a BGP route to be usable, the receiving router must generally be able to resolve that next-hop address through its routing information. AS_PATH records the autonomous systems traversed, MED can influence certain inbound path decisions, and Origin indicates how the route entered BGP. NEXT_HOP therefore directly describes the address associated with forwarding toward the BGP-advertised destination.

Question: 395. Which IPv4 address range is reserved for private networks in the 192.168/16 block?

1. 192.168.0.0/16
   2. 169.254.0.0/16
   3. 172.16.0.0/12
   4. 224.0.0.0/4

Correct Answer: 1. 192.168.0.0/16

Explanation:

The 192.168.0.0/16 prefix is an RFC 1918 private IPv4 address range. It covers addresses from 192.168.0.0 through 192.168.255.255 and is widely used for private LAN addressing. The other RFC 1918 ranges are 10.0.0.0/8 and 172.16.0.0/12. 169.254.0.0/16 is associated with IPv4 link-local addressing, while 224.0.0.0/4 is the IPv4 multicast range. Private addresses are intended for internal networks and are not directly routable across the public Internet.

Question: 396. Which OSPF neighbor state indicates that two routers have fully synchronized their link-state databases?

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

Correct Answer: 2. Full

Explanation:

The OSPF Full state indicates that two routers have completed the database synchronization process and have formed a fully established adjacency. Their relevant link-state information has been exchanged and synchronized. The Init state indicates that a Hello has been received without confirmed bidirectional communication, while 2-Way indicates bidirectional communication but does not necessarily result in a full adjacency. Exchange is the stage where Database Description packets are exchanged before the routers request and receive the required LSAs.

Question: 397. Which Junos command is used to view active system alarms?

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

Correct Answer: 3. show system alarms

Explanation:

The show system alarms command displays active alarms reported by the Junos device. These alarms can identify hardware, environmental, or other system-level conditions that may require investigation. show chassis hardware provides hardware inventory, show system uptime provides runtime information, and show interfaces terse displays a concise interface status summary. When the objective is specifically to determine whether the system currently reports active alarms, show system alarms is the appropriate command.

Question: 398. Which technology dynamically negotiates and maintains a link aggregation group between compatible devices?

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

Correct Answer: 1. LACP

Explanation:

LACP, or Link Aggregation Control Protocol, dynamically negotiates and maintains link aggregation between compatible devices. It allows multiple physical Ethernet links to participate in a logical aggregated interface, providing additional bandwidth and redundancy. LACP also helps detect whether participating links are properly associated with the aggregation group. VRRP provides first-hop gateway redundancy, BFD provides rapid failure detection, and GRES supports Routing Engine switchover. LACP is therefore the technology specifically associated with dynamically managing aggregated Ethernet links.

Question: 399. Which BGP attribute is used to prevent routing loops between autonomous systems?

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

Correct Answer: 2. AS_PATH

Explanation:

The BGP AS_PATH attribute provides a fundamental mechanism for preventing routing loops between autonomous systems. As a route advertisement crosses autonomous systems, the AS numbers are recorded in the AS_PATH. If a BGP router receives a route containing its own AS number in the path, it can reject that route as a looped advertisement. AS_PATH length can also influence path selection, with shorter paths generally preferred when the relevant earlier criteria are equal. Local Preference, MED, and NEXT_HOP perform different functions in BGP operation.

Question: 400. Which Junos command provides a summary of BGP peer sessions and their current states?

1. show route protocol bgp
   2. show bgp summary
   3. show ospf neighbor
   4. show route <prefix> detail

Correct Answer: 2. show bgp summary

Explanation:

The show bgp summary command provides a concise overview of BGP peer sessions and their operational states. It can show information such as peer addresses, autonomous system numbers, message statistics, and the number of prefixes received. This makes it a useful first command when troubleshooting BGP peering. show route protocol bgp focuses on routes learned through BGP, show ospf neighbor displays OSPF adjacencies, and show route <prefix> detail provides detailed information about a particular route rather than a summary of BGP sessions.