Juniper JN0-105 Online Practice Questions and Exam Preparation

Juniper JN0-105 Online Questions & Answers

• Question 1:

  Which two statements describe the functions of the Packet Forwarding Engine (PFE)? (Choose two.)

  A. The PFE will route or switch packets or frames out of the correct interface as quickly as possible.
  B. The PFE will apply filters and routing policies when forwarding the packets to their final destination.
  C. A The PFE will process management traffic to help monitor and manage the network device.
  D. A The PFE will calculate the best network path to each individual subnet based on input from various routing protocols and static routes.
  A. The PFE will route or switch packets or frames out of the correct interface as quickly as possible.
  B. The PFE will apply filters and routing policies when forwarding the packets to their final destination.

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  Explanation

• Question 2:

  What are two types of transit traffic that traverse the forwarding plane of a Layer 3 router? (Choose two.)

  A. exception traffic
  B. broadcast traffic
  C. unicast traffic
  D. multicast traffic
  C. unicast traffic
  D. multicast traffic

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  Explanation

  Transit traffic that traverses the forwarding plane of a Layer 3 router includes both unicast and multicast traffic types. Unicast traffic is directed from a single source to a single destination, while multicast traffic is sent from one source to multiple destinations that are part of a multicast group. These types of traffic are efficiently routed through the network by leveraging the router's forwarding plane capabilities. Exception traffic, which requires special handling by the control plane, and broadcast traffic, which is typically limited to a single broadcast domain and not usually forwarded by Layer 3 routers, are not considered standard types of transit traffic for the forwarding plane of a router.

• Question 3:

  Which two statements about firewall filters are correct? (Choose two.)

  A. Firewall filters can match Layer 7 parameters.
  B. Firewall filters are stateless.
  C. Firewall filters are stateful.
  D. Firewall filters can match Layer 4 parameters.
  B. Firewall filters are stateless.
  D. Firewall filters can match Layer 4 parameters.

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  Explanation

  Firewall filters in Junos OS are stateless, meaning they process each packet individually without regard to the state of a connection or sequence of packets. These filters can match various packet attributes, including those at Layer 4, such as TCP and UDP port numbers. This allows for granular control over traffic based on the type of service or application. Unlike stateless filters, stateful firewalls keep track of the state of active connections and make decisions based on the context of the traffic flow, which is not a capability of Junos firewall filters. Additionally, Junos firewall filters primarily operate up to Layer 4 and do not natively inspect Layer 7 parameters, which involve application-level data.

• Question 4:

  What is the maximum number of rollback configuration files that the Junos OS will store?

  A. 25
  B. 65
  C. 50
  D. 19
  C. 50

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  Explanation

  Junos OS can store up to 50 rollback configuration files, making C the correct answer. These rollback files allow administrators to revert to previous configurations, providing a safety net that facilitates recovery from configuration errors or undesired changes

• Question 5:

  An administrator configures a router's interface with an IPv4 address and subnet mask. The administrator also confirms that this interface is in an up state.

  In this scenario, which two route types are created on the local router? (Choose two.)

  A. a static route
  B. a local route
  C. a dynamic route
  D. a direct route
  B. a local route
  D. a direct route

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  Explanation

  When an interface on a router is configured with an IPv4 address and is in an up state, two types of routes are automatically created in the routing table: a local route and a direct route, making B and D the correct answers. The local route represents the interface's IP address itself, indicating that the router can directly receive packets addressed to this IP. The direct route represents the subnet or network segment to which the interface is connected, indicating that the router can directly forward packets to destinations within this subnet.

• Question 6:

  What is the purpose of the load merge command?

  A. to add or delete variables from the configuration based on the contents of a specified path file.
  B. to completely overwrite the current configuration with the configuration you load.
  C. to combine the current configuration with the configuration you load.
  D. to look for a replace tag in the configuration you load.
  C. to combine the current configuration with the configuration you load.

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  Explanation

• Question 7:

  Click the Exhibit button.

  

  Referring to the exhibit, OSPF has three export policies that match different static route prefixes. The 10.10.10.0/24 static route does not match any terms in the policy1 routing policy.

  What happens next in this scenario?

  A. The static route is rejected by the default routing policy.
  B. The static route is rejected by the policy1 routing policy.
  C. The static route is evaluated by the policy2 routing policy.
  D. The static route is evaluated by the policy3 routing policy.
  C. The static route is evaluated by the policy2 routing policy.

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  Explanation

  In Junos, when multiple policies are applied to a routing protocol for route export, the routes are evaluated in the order in which the policies are listed. In the exhibit, the OSPF configuration has three export policies listed: policy1, policy2, and policy3. The static route 10.10.10.0/24 does not match any terms in policy1; therefore, it is not rejected by policy1 but is instead passed on to the next policy in the sequence, which is policy2. If the static route matches a term in policy2 that permits the route, it will be exported into OSPF. If it does not match in policy2, it will then be evaluated by policy3. If there is no match in policy3 as well, and assuming there are no more policies listed, the route would then be subject to the default routing policy behavior, which typically rejects the route unless an explicit accept statement is present in the policies.

• Question 8:

  Which two statements are correct about firewall filters? (Choose two.)

  A. "Discard" is the default action of packets that are not explicitly allowed.
  B. There can be only one firewall filter.
  C. There can be multiple firewall filters.
  D. "Accept" is the default action of packets that are not explicitly allowed.
  A. "Discard" is the default action of packets that are not explicitly allowed.
  C. There can be multiple firewall filters.

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  Explanation

  In Juniper Networks devices, firewall filters are used to control packet flow through the device. The default action for packets that do not match any of the specified criteria in the firewall filter is to discard them, enhancing network security by ensuring that only explicitly allowed traffic can pass through. Furthermore, it is possible to configure multiple firewall filters on a device, allowing for granular control over traffic based on various criteria such as source, destination, and protocol type.

• Question 9:

  Which process in the Junos OS is responsible for maintaining routing protocols and tables?

  A. mgd
  B. chassisd
  C. dcd
  D. rpd
  D. rpd

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  Explanation

  The Routing Protocol Daemon (rpd) in Junos OS is responsible for maintaining routing protocols and tables. It handles all routing information, including the calculation of routes and the population of the routing table, making it crucial for dynamic routing operations.

• Question 10:

  Which two common routing policy actions affect the flow of policy evaluation? (Choose two.)

  A. next term
  B. next hop
  C. next policy
  D. community
  A. next term
  C. next policy

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  Explanation

  In Junos OS routing policy evaluation, "next policy" and "next term" are common actions that affect the flow of policy evaluation. "Next policy" directs the evaluation to the next policy in the sequence, whereas "next term" moves the evaluation to the next term within the current policy, allowing for granular control over routing decisions.