Juniper JN0-351 Online Practice Questions and Exam Preparation

Juniper JN0-351 Online Questions & Answers

• Question 71:

  Two routers share the same highest priority and start time.

  A. In this situation, what is evaluated next when determining the designated router? The router with the lowest router ID become the DR.
  B. The router with the highest router ID becomes the DR
  C. The routers perform another DR election.
  D. The router with the highest MAC address become the DR
  B. The router with the highest router ID becomes the DR

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  Explanation/Reference:

  According to the OSPF protocol, the designated router (DR) is the router that acts as the focal point for exchanging routing information on a multi-access network segment, such as a LAN1. The DR election process is based on the following

  criteria, in order of precedence1:

  In your scenario, two routers share the same highest priority and start time. This means that they have equal chances of becoming the DR based on the first and third criteria. Therefore, the second criterion will be used to break the tie, which

  is the router ID. The router with the highest router ID will become the DR, and the other router will become the backup designated router (BDR), which is ready to take over the role of DR if it fails1.

• Question 72:

  Exhibit.

  

  You are using OSPF to advertise the subnets that are used by the Denver and Dallas offices. The routers that are directly connected to the Dallas and Denver subnets are not advertising the connected subnets.

  Referring to the exhibit, which two statements are correct? (Choose two.)

  A. Create static routes on the switches using the local vMX router's loopback interface for the next hop.
  B. Configure and apply a routing policy that redistributes the Dallas and Denver subnets using Type 5 LSAs.
  C. Configure and apply a routing policy that redistributes the connected Dallas and Denver subnets.
  D. Enable the passive option on the OSPF interfaces that are connected to the Dallas and Denver subnets.
  C. Configure and apply a routing policy that redistributes the connected Dallas and Denver subnets.
  D. Enable the passive option on the OSPF interfaces that are connected to the Dallas and Denver subnets.

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  Explanation/Reference:

  The routers that are directly connected to the Dallas and Denver subnets are not advertising the connected subnets. This can be resolved by redistributing the connected subnets into OSPF1.

  Option C suggests to configure and apply a routing policy that redistributes the connected Dallas and Denver subnets. This is correct because redistribution allows routes from one routing protocol to be communicated to another, and in this

  case, it allows the connected subnets to be advertised through OSPF1.

  Option D suggests enabling the passive option on the OSPF interfaces that are connected to the Dallas and Denver subnets. This is also correct because in OSPF, a passive interface is an interface that belongs to the OSPF router, but does

  not send OSPF Hello packets1. It's typically used on an interface that you don't want to use for OSPF adjacencies, but you still want to advertise its IP address1. Therefore, enabling passive interface can help in advertising the Dallas and

  Denver subnets.

• Question 73:

  Click the Exhibit button.

  

  Your company has connections to two ISPs. Each ISP is in a separate routing instance. You need to advertise the 0.0.0.0/0 prefix from both ISPs to all your devices.

  Referring to the exhibit, which statement is true in this scenario?

  A. You must create and apply match input filters on interfaces ge-0/0/2 and ge-0/0/3.
  B. You must create a policy to allow traffic from your network to each ISP.
  C. You must create an internal routing instance for your network.
  D. You must create a RIB group to share interface routes.
  D. You must create a RIB group to share interface routes.

• Question 74:

  You are deploying a new switch configuration at a small branch using EX3400 Series switches. You are concerned about loop prevention.

  In this scenario, which configuration would you deploy?

  A. RSTP
  B. EVPN
  C. MPLS D. BPDU
  A. RSTP

• Question 75:

  Referring to the exhibit, which interface is assigned the active VIP?

  

  A. Router A ge-0/0/2
  B. Router B ge-0/0/1
  C. Router A ge-0/0/1
  D. Router B ge-0/0/2
  B. Router B ge-0/0/1

• Question 76:

  Exhibit.

  

  You are attempting to set up VRRP with R1 and R2 being participating members. You want R1 to be the master router and R2 to be the backup router with the virtual router they create being at address 172.25.100.1. The virtual router is not pinging from either User A or User B.

  Referring to the exhibit, what must be done to correct the problem?

  A. The VRRP group value on R1 and R2 must match.
  B. A VRRP authentication type value is needed on R1 and R2.
  C. A VRRP policy is needed on R1 and R2.
  D. The VRRP priority value on R1 and R2 must match
  A. The VRRP group value on R1 and R2 must match.

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  Explanation/Reference:

  https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration- statement/priority-edit-interfaces-vrrp.html

• Question 77:

  An update to your organization's network security requirements document requires management traffic to be isolated in a non-default routing-instance. You want to implement this requirement on your Junos-based devices.

  Which two commands enable this behavior? (Choose two.)

  A. set routing--instances mgmtjunoa interface ge-0/0/0.0
  B. set routing--instances mgmt_junos interface em1
  C. set system management--instance
  D. set routing--instances mgmt_junos
  C. set system management--instance
  D. set routing--instances mgmt_junos

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  Explanation/Reference:

  To isolate management traffic in a non-default routing-instance on Junos- based devices, you can use the set system management-instance and set routing- instances mgmt_junos commands12.

  set system management-instance: This command associates the management interface (usually named fxp0 or em0 for Junos OS, or re0:mgmt-* or re1:mgmt-* for Junos OS Evolved) with the non-default virtual routing and forwarding (VRF)

  instance1. After you configure the non-default management VRF instance, management traffic no longer has to share a routing table with other control traffic or protocol traffic1.

  set routing-instances mgmt_junos: This command creates a new routing instance named mgmt_junos. The name of the dedicated management VRF instance is reserved and hardcoded as mgmt_junos; you cannot configure any other routing

  instance by the name mgmt_junos1.

  Therefore, options C and D are correct. Options A and B are not correct because they attempt to assign an interface to the mgmt_junos routing instance, which is not necessary for isolating management traffic1.

• Question 78:

  The router ID is not configured.

  How does OSPFv3 determine the router ID in this situation?

  A. OSPFv3 uses the IPv4 address of the first interface that comes up.
  B. OSPFv3 uses the IPv6 address of the last interface that comes up.
  C. OSPFv3 uses the IPv6 address of the first interface that comes up.
  D. OSPFv3 uses the IPv4 address of the last interface that comes up.
  A. OSPFv3 uses the IPv4 address of the first interface that comes up.

• Question 79:

  Which two statements about BGP facilitate the prevention of routing loops between two autonomous systems? (Choose two.)

  A. EBGP routers will append their AS number when advertising routes to their neighbors.
  B. EBGP routers will only accept routes that contain their own AS number in the AS_PATH.
  C. EBGP routers will drop routes that contain their own AS number in the AS_PATH
  D. EBGP routers will prepend their AS number when advertising routes to their neighbors
  A. EBGP routers will append their AS number when advertising routes to their neighbors.
  C. EBGP routers will drop routes that contain their own AS number in the AS_PATH

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  Explanation/Reference:

  BGP (Border Gateway Protocol) is a protocol designed to exchange routing and reachability information among autonomous systems (AS) on the internet1. Option A is correct. When an EBGP router advertises routes to its

  neighbors, it appends its AS number to the AS_PATH attribute1. This is a key mechanism in BGP to prevent routing loops1.

  Option C is correct. BGP has a built-in loop prevention mechanism whereby if a BGP router detects its own AS in the AS_PATH attribute, it will drop the prefix and will not continue to advertise it2. This helps to prevent routing loops2. Option B

  is incorrect. EBGP routers do not accept routes that contain their own AS number in the AS_PATH2. Instead, they drop such routes as part of the loop prevention mechanism2.

  Option D is incorrect. While it's true that EBGP routers append their AS number when advertising routes, they do not prepend their AS number1. The term "prepend" in BGP usually refers to a technique used to influence path selection by

  artificially lengthening the AS_PATH3.

• Question 80:

  You have a VLAN with two devices acting as a single gateway for hosts.

  In this scenario, which protocol would provide a single gateway IP for the hosts?

  A. VRRP
  B. OSPF
  C. IS-IS
  D. BGP
  A. VRRP