Practice Free JN0-280 Exam Online Questions
Question #31
What is the default route preference of a static route in the Junos OS?
- A . 0
- B . 10
- C . 1
- D . 5
Correct Answer: D
D
Explanation:
In Junos OS, the default route preference for a static route is 5. Route preference values are used to determine which route should be installed in the routing table when multiple routes to the same destination are available.
Step-by-Step Breakdown:
Static Route Preference:
A static route, by default, has a preference of 5, making it a highly preferred route. Lower preference values are more preferred in Junos, meaning static routes take precedence over most dynamic routing protocol routes, such as OSPF (preference 10) or BGP (preference 170).
Route Preference:
Route preference is a key factor in the Junos routing decision process. Routes with lower preference values are preferred and installed in the forwarding table.
Juniper
Reference: Static Routes: In Junos, the default preference for static routes is 5, making them more preferred than most dynamic routes.
D
Explanation:
In Junos OS, the default route preference for a static route is 5. Route preference values are used to determine which route should be installed in the routing table when multiple routes to the same destination are available.
Step-by-Step Breakdown:
Static Route Preference:
A static route, by default, has a preference of 5, making it a highly preferred route. Lower preference values are more preferred in Junos, meaning static routes take precedence over most dynamic routing protocol routes, such as OSPF (preference 10) or BGP (preference 170).
Route Preference:
Route preference is a key factor in the Junos routing decision process. Routes with lower preference values are preferred and installed in the forwarding table.
Juniper
Reference: Static Routes: In Junos, the default preference for static routes is 5, making them more preferred than most dynamic routes.
Question #32
Which OSPF troubleshooting tool is used to check the OSPF process and neighborship?
- A . Traceoptions
- B . Ping
- C . Route summarization
- D . SNMP
Correct Answer: A
Question #33
What are three correct layer names used in legacy hierarchical network design? (Choose three.)
- A . Access layer
- B . Modular layer
- C . Aggregation layer
- D . Core layer
- E . Function layer
Correct Answer: A, C, D
A, C, D
Explanation:
In legacy hierarchical network design, three key layers are used to create a scalable and structured
network:
Step-by-Step Breakdown:
Access Layer:
The access layer is where end devices, such as computers and IP phones, connect to the network. It typically involves switches that provide connectivity for devices at the edge of the network. Aggregation Layer (Distribution Layer):
The aggregation layer (also called the distribution layer) aggregates traffic from multiple access layer devices and applies policies such as filtering and QoS. It also provides redundancy and load balancing.
Core Layer:
The core layer provides high-speed connectivity between aggregation layer devices and facilitates traffic within the data center or between different network segments. Juniper
Reference: Legacy Hierarchical Design: Juniper networks often follow the traditional three-layer design (Access, Aggregation, and Core) to ensure scalability and high performance.
A, C, D
Explanation:
In legacy hierarchical network design, three key layers are used to create a scalable and structured
network:
Step-by-Step Breakdown:
Access Layer:
The access layer is where end devices, such as computers and IP phones, connect to the network. It typically involves switches that provide connectivity for devices at the edge of the network. Aggregation Layer (Distribution Layer):
The aggregation layer (also called the distribution layer) aggregates traffic from multiple access layer devices and applies policies such as filtering and QoS. It also provides redundancy and load balancing.
Core Layer:
The core layer provides high-speed connectivity between aggregation layer devices and facilitates traffic within the data center or between different network segments. Juniper
Reference: Legacy Hierarchical Design: Juniper networks often follow the traditional three-layer design (Access, Aggregation, and Core) to ensure scalability and high performance.
Question #34
Under which Junos hierarchy is a static route configured?
- A . system
- B . routing-instances
- C . routing-options
- D . protocols
Correct Answer: C
Question #35
Which statement is correct about an IP fabric?
- A . Transit traffic is passed through the network based on the original frame’s destination MAC address.
- B . Load sharing is provided by the routing protocol used.
- C . Loop prevention is provided by the underlying spanning tree protocol used.
- D . The entire IP fabric is one large broadcast domain.
Correct Answer: B
Question #36
What statement is true about load-balancing?
- A . Load balancing is only supported after applying an advanced license.
- B . Load balancing on Juniper devices is processed per-packet.
- C . Load balancing on Juniper devices is processed per-flow.
- D . Load balancing is only supported by dynamic routing protocols.
Correct Answer: C
Question #37
Which of the following statements are true regarding Graceful Restart (GR)? (Choose two)
- A . It helps in maintaining uninterrupted forwarding during a routing process restart.
- B . It is used to increase the convergence time of the network.
- C . It requires support from both the restarting router and its neighbors.
- D . It decreases network stability during protocol restarts.
Correct Answer: AC
Question #38
Which two statements are correct about BGP? (Choose two.)
- A . IBGP peers do not advertise routes learned from IBGP peers to other IBGP peers.
- B . EBGP uses the AS path to avoid loops.
- C . IBGP sessions are typically established between physical router interfaces.
- D . EBGP sessions are typically established between router loopback interfaces.
Correct Answer: AB
Question #39
What are two device roles in a five-member Virtual Chassis? (Choose two.)
- A . PFE
- B . Control-board
- C . Line card
- D . Routing-engine
Correct Answer: C, D
C, D
Explanation:
In a Virtual Chassis (VC) configuration, multiple Juniper switches are interconnected to form a single logical device. Each member switch in the Virtual Chassis plays a specific role. Step-by-Step Breakdown:
Line Card Role:
Member switches acting as line cards provide additional ports for traffic forwarding but do not perform control or routing functions. These switches depend on the routing engine to handle control-plane tasks.
Routing Engine Role:
A switch in the routing-engine role is responsible for control-plane operations such as routing protocol management and control of the Virtual Chassis.
Virtual Chassis Roles:
Master Routing Engine: Handles control-plane functions and manages the entire Virtual Chassis.
Backup Routing Engine: Takes over if the master fails.
Line Card: Provides additional ports and handles data-plane operations. Juniper
Reference: Virtual Chassis: In a five-member Virtual Chassis, multiple switches act as line cards, while one or more switches are designated as the routing engines (master and backup).
C, D
Explanation:
In a Virtual Chassis (VC) configuration, multiple Juniper switches are interconnected to form a single logical device. Each member switch in the Virtual Chassis plays a specific role. Step-by-Step Breakdown:
Line Card Role:
Member switches acting as line cards provide additional ports for traffic forwarding but do not perform control or routing functions. These switches depend on the routing engine to handle control-plane tasks.
Routing Engine Role:
A switch in the routing-engine role is responsible for control-plane operations such as routing protocol management and control of the Virtual Chassis.
Virtual Chassis Roles:
Master Routing Engine: Handles control-plane functions and manages the entire Virtual Chassis.
Backup Routing Engine: Takes over if the master fails.
Line Card: Provides additional ports and handles data-plane operations. Juniper
Reference: Virtual Chassis: In a five-member Virtual Chassis, multiple switches act as line cards, while one or more switches are designated as the routing engines (master and backup).
Question #40
In OSPF, which term refers to routers that have interfaces in multiple areas?
- A . Internal Routers
- B . Backbone Routers
- C . Area Border Routers (ABRs)
- D . Autonomous System Boundary Routers (ASBRs)
Correct Answer: C