Juniper JN0-364\u00a0 Exam Dumps<\/b><\/a> and Practice Test Dumps<\/b><\/p>\n <\/p>\n
Question: 41. Which Junos operational command can be used to view the status of a BGP session and summarize information about BGP peers?<\/b><\/p>\n\n- <\/b> show ospf interface<\/span>
\n<\/span>2.<\/b> show bgp summary<\/span>
\n<\/span>3.<\/b> show route forwarding-table<\/span>
\n<\/span>4.<\/b> show ethernet-switching table<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 2. show bgp summary<\/span><\/p>\nExplanation:<\/b><\/p>\n
The <\/span>show bgp summary<\/span> command provides a concise overview of BGP peers and their session status. It can display information such as the local autonomous system, configured neighbors, peer state, number of routes received, and other session-related details. This makes it particularly useful when determining whether BGP sessions are established and exchanging routing information. <\/span>show ospf interface<\/span> focuses on OSPF interfaces, while forwarding-table and Ethernet-switching commands provide information about forwarding and Layer 2 switching. When troubleshooting BGP, the summary command is often an effective starting point before examining detailed routes or policies.<\/span><\/p>\nQuestion: 42. Which BGP attribute is normally considered first among the listed attributes when selecting a preferred route on a Junos device?<\/b><\/p>\n\n- <\/b> Local preference<\/span>
\n<\/span>2.<\/b> MED<\/span>
\n<\/span>3.<\/b> Origin<\/span>
\n<\/span>4.<\/b> Router ID<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 1. Local preference<\/span><\/p>\nExplanation:<\/b><\/p>\n
Local preference is an important BGP attribute used to influence outbound route selection within an autonomous system. In the Junos BGP route-selection process, a higher local-preference value is generally preferred when comparing otherwise eligible routes. It is commonly used to control which external exit point the autonomous system should use. MED, origin, and router ID are considered at different stages of route selection. Local preference is propagated through iBGP and is therefore particularly useful for establishing consistent outbound-routing policies across an organization. BGP policy can modify local preference to implement deliberate traffic-engineering decisions.<\/span><\/p>\nQuestion: 43. Which protocol provides a loop-prevention mechanism by recording the autonomous systems a BGP route has traversed?<\/b><\/p>\n\n- <\/b> OSPF<\/span>
\n<\/span>2.<\/b> LACP<\/span>
\n<\/span>3.<\/b> BGP<\/span>
\n<\/span>4.<\/b> VRRP<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 3. BGP<\/span><\/p>\nExplanation:<\/b><\/p>\n
BGP uses the AS path attribute to record the sequence of autonomous systems through which a route advertisement has passed. This provides an important loop-prevention mechanism. When an autonomous system receives a route advertisement containing its own AS number in the AS path, the route can be rejected because accepting it could create an inter-AS routing loop. The AS path is also considered during BGP route selection. OSPF prevents loops through its link-state topology and SPF calculation, while LACP and VRRP serve link aggregation and gateway-redundancy functions respectively.<\/span><\/p>\nQuestion: 44. What does the Junos command <\/b>show route forwarding-table<\/b> primarily display?<\/b><\/p>\n\n- <\/b> BGP policy configuration<\/span>
\n<\/span>2.<\/b> OSPF neighbor states<\/span>
\n<\/span>3.<\/b> Candidate configuration changes<\/span>
\n<\/span>4.<\/b> Packet-forwarding information installed for forwarding traffic<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 4. Packet-forwarding information installed for forwarding traffic<\/span><\/p>\nExplanation:<\/b><\/p>\n
The <\/span>show route forwarding-table<\/span> command provides information about the forwarding table used to make actual packet-forwarding decisions. The routing table contains routing information learned from connected interfaces, static routes, and routing protocols, while the forwarding table represents information programmed for packet forwarding. Examining the forwarding table can be especially useful when a route appears correctly installed in the routing table but traffic does not behave as expected. OSPF neighbor commands, BGP policy configuration, and candidate configuration information serve different troubleshooting purposes and do not directly display the forwarding table.<\/span><\/p>\nQuestion: 45. Which OSPF packet type is used to request specific link-state information from a neighboring router?<\/b><\/p>\n\n- <\/b> Link-State Request<\/span>
\n<\/span>2.<\/b> Database Description<\/span>
\n<\/span>3.<\/b> Link-State Acknowledgment<\/span>
\n<\/span>4.<\/b> Hello<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 1. Link-State Request<\/span><\/p>\nExplanation:<\/b><\/p>\n
An OSPF Link-State Request, or LSR, is used when a router needs specific link-state information from a neighbor. During database synchronization, routers compare the information they know and can request missing or newer LSAs using LSR packets. The neighbor responds with Link-State Update packets containing the requested information. Database Description packets summarize the contents of a router’s link-state database, while Hello packets establish and maintain neighbor relationships. Link-State Acknowledgment packets confirm receipt of LSAs. Understanding the five OSPF packet types is useful when diagnosing adjacency and database-synchronization problems.<\/span><\/p>\nQuestion: 46. Which Junos configuration mode is used to make changes to the candidate configuration before they are activated?<\/b><\/p>\n\n- <\/b> Shell mode<\/span>
\n<\/span>2.<\/b> Operational mode<\/span>
\n<\/span>3.<\/b> Configuration mode<\/span>
\n<\/span>4.<\/b> Monitor mode<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 3. Configuration mode<\/span><\/p>\nExplanation:<\/b><\/p>\n
Junos uses configuration mode for creating, modifying, and reviewing the candidate configuration. Changes made in this mode are not normally active in the forwarding configuration until they are committed. This separation allows administrators to review and validate changes before applying them. Operational mode is primarily used for monitoring and troubleshooting the running device. Junos also provides commands such as <\/span>commit check<\/span> to validate configuration syntax and <\/span>commit<\/span> to activate changes. Understanding the separation between operational and configuration modes is fundamental to safe Junos administration and helps reduce accidental changes to production services.<\/span><\/p>\nQuestion: 47. Which routing protocol is classified as a distance-vector protocol and traditionally uses hop count as its routing metric?<\/b><\/p>\n\n- <\/b> OSPF<\/span>
\n<\/span>2.<\/b> RIP<\/span>
\n<\/span>3.<\/b> IS-IS<\/span>
\n<\/span>4.<\/b> BGP<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 2. RIP<\/span><\/p>\nExplanation:<\/b><\/p>\n
Routing Information Protocol, or RIP, is a distance-vector routing protocol that traditionally uses hop count as its primary routing metric. Each router exchanges routing information with neighbors and selects paths based largely on the number of router hops. RIP has a relatively small maximum hop-count limit, which limits its suitability for large networks. OSPF and IS-IS are link-state protocols, while BGP is a path-vector protocol that uses multiple attributes for route selection. Although RIP is less common in modern large-scale enterprise and service-provider networks, understanding its behavior remains useful for networking fundamentals and certification exams.<\/span><\/p>\nQuestion: 48. What is the primary purpose of a Junos routing policy?<\/b><\/p>\n\n- <\/b> Replace the forwarding engine<\/span>
\n<\/span>2.<\/b> Establish Ethernet cabling standards<\/span>
\n<\/span>3.<\/b> Control how routes are imported, exported, accepted, rejected, or modified<\/span>
\n<\/span>4.<\/b> Provide physical interface redundancy<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 3. Control how routes are imported, exported, accepted, rejected, or modified<\/span><\/p>\nExplanation:<\/b><\/p>\n
Junos routing policies provide a flexible mechanism for controlling route processing. Policies can match characteristics such as protocol, prefix, community, route attributes, or other criteria and then apply actions such as accepting, rejecting, modifying, or changing route attributes. Routing policies are commonly used with BGP, OSPF, IS-IS, and route redistribution. They allow administrators to implement deliberate routing behavior rather than relying only on default protocol decisions. Routing policies do not replace forwarding hardware or provide physical link redundancy. Understanding policy terms, match conditions, and actions is essential for Junos routing configuration and troubleshooting.<\/span><\/p>\nQuestion: 49. Which BGP community is commonly used to prevent a route from being advertised to BGP peers?<\/b><\/p>\n\n- <\/b> no-export<\/span>
\n<\/span>2.<\/b> internet<\/span>
\n<\/span>3.<\/b> local-AS<\/span>
\n<\/span>4.<\/b> no-advertise<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 4. no-advertise<\/span><\/p>\nExplanation:<\/b><\/p>\n
The well-known BGP <\/span>no-advertise<\/span> community indicates that a route should not be advertised to any BGP peer. This provides a mechanism for controlling route propagation through BGP policy. The <\/span>no-export<\/span> community has a different scope: it generally prevents a route from being advertised outside the local autonomous system or confederation context according to the applicable rules. The <\/span>internet<\/span> community indicates that the route may be advertised to all BGP peers, while <\/span>local-AS<\/span> has specific behavior associated with confederations or local-AS configurations. Communities are therefore powerful tools for implementing routing policy.<\/span><\/p>\nQuestion: 50. Which IPv4 prefix is reserved for private addressing in the 172.16.0.0 range?<\/b><\/p>\n\n- <\/b> 172.0.0.0\/12<\/span>
\n<\/span>2.<\/b> 172.16.0.0\/12<\/span>
\n<\/span>3.<\/b> 172.32.0.0\/12<\/span>
\n<\/span>4.<\/b> 172.16.0.0\/16<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 2. 172.16.0.0\/12<\/span><\/p>\nExplanation:<\/b><\/p>\n
The IPv4 private address block <\/span>172.16.0.0\/12<\/span> covers addresses from <\/span>172.16.0.0<\/span> through <\/span>172.31.255.255<\/span>. These addresses are intended for private network use and are not globally routable on the public Internet. The other private IPv4 blocks are <\/span>10.0.0.0\/8<\/span> and <\/span>192.168.0.0\/16<\/span>. The distinction between <\/span>172.16.0.0\/12<\/span> and smaller prefixes such as <\/span>\/16<\/span> is important because the entire <\/span>\/12<\/span> range is reserved for private addressing. Private addresses are commonly used inside enterprise networks and may require NAT or another mechanism when communicating with public networks.<\/span><\/p>\nQuestion: 51. What is the primary function of an OSPF Link-State Update packet?<\/b><\/p>\n\n- <\/b> Carry one or more LSAs to neighboring routers<\/span>
\n<\/span>2.<\/b> Establish the TCP session used by OSPF<\/span>
\n<\/span>3.<\/b> Assign IP addresses to OSPF interfaces<\/span>
\n<\/span>4.<\/b> Negotiate Ethernet link aggregation<\/span><\/li>\n<\/ol>\n