Best Way To Study For Juniper JN0-351 Exam Brilliant JN0-351 Exam Questions PDF
Updated Verified Pass JN0-351 Exam - Real Questions and Answers
NEW QUESTION # 21
Which two BGP attributes must be supported by all BGP implementations and must be included in every update? (Choose two.)
- A. next hop
- B. MED
- C. AS path
- D. community
Answer: A,C
Explanation:
Explanation
BGP attributes are properties that BGP uses for route advertisement, path selection, and loop prevention1. There are four categories of BGP attributes123:
Well-known mandatory: Must be recognized by all BGP routers, present in all BGP updates, and passed on to other BGP routers123.
Well-known discretionary: Supported by all BGP implementations, and are optionally included in BGP updates1.
Optional transitive: May not be supported by all implementations of BGP1.
Optional non-transitive: May not be supported by all implementations of BGP1.
The well-known mandatory attributes must be supported by all BGP implementations and must be included in every update123. These include the AS path and next hop attributes23. Therefore, options A and C are correct.
NEW QUESTION # 22
You deployed a new EX Series switch with DHCP snooping enabled and you do not see any entries in the snooping databases for an interface. Which two Juniper configurations for that interface caused this issue?
(Choose two.)
- A. The interface is configured as a trunk port.
- B. Dynamic ARP inspection is enabled on the interface.
- C. MAC limiting is enabled on the interface.
- D. The interface is configured as a disabled port.
Answer: A,D
Explanation:
A is correct because the interface is configured as a disabled port. A disabled port does not forward any traffic, including DHCP packets. Therefore, DHCP snooping cannot learn any MAC addresses or lease information from a disabled port1.
C is correct because the interface is configured as a trunk port. By default, all trunk ports on the switch are trusted for DHCP snooping2. This means that DHCP snooping does not inspect or filter any DHCP packets received on a trunk port. Therefore, DHCP snooping does not add any entries to the snooping database for a trunk port2.
NEW QUESTION # 23
You are configuring an IS-IS IGP network and do not see the IS-IS adjacencies established. In this scenario, what are two reasons for this problem? (Choose two.)
- A. MTU is not at least 1492 bytes.
- B. The lo0 interface is not included as an IS-IS interface.
- C. IP subnets are not a /30 address.
- D. The Level 2 routers have mismatched areas.
Answer: A,B
Explanation:
Explanation
Option A suggests that the MTU is not at least 1492 bytes. This is correct because IS-IS requires a minimum MTU of 1492 bytes to establish adjacencies1. If the MTU is less than this, IS-IS adjacencies will not be established1.
Option D suggests that the lo0 interface is not included as an IS-IS interface. This is also correct because the loopback interface (lo0) is typically used as the router ID in IS-IS1. If the loopback interface is not included in IS-IS, it could prevent IS-IS adjacencies from being established1.
Therefore, options A and D are correct.
NEW QUESTION # 24
In RSTP, which three port roles are associated with the discarding state? (Choose three.)
- A. designated
- B. alternate
- C. backup
- D. disabled
- E. root
Answer: B,C,D
Explanation:
Explanation
In Rapid Spanning Tree Protocol (RSTP), there are several port roles that determine the behavior of the port in the spanning tree123. The roles include root, designated, alternate, backup, and disabled123.
The discarding state is associated with the backup, alternate, and disabled roles123. In a stable topology with consistent port roles throughout the network, RSTP ensures that every root port and designated port immediately transition to the forwarding state while all alternate and backup ports are always in the discarding state2. Disabled ports are also in the discarding state3.
Therefore, options B, C, and D are correct.
NEW QUESTION # 25
Exhibit
What does the * indicate in the output shown in the exhibit?
- A. The switch ports have a router attached.
- B. The interface is active.
- C. The interface is down.
- D. All interfaces have elected a root bridge.
Answer: B
Explanation:
The exhibit shows the output of the command show vlans brief, which displays brief information about VLANs and their associated interfaces1.
The output has four columns: Routing instance, VLAN name, Interfaces, and Tagging.
The * symbol indicates that the interface is active, meaning that it is up and forwarding traffic1. This can be verified by the command , which displays the status of the interfaces2.
NEW QUESTION # 26
Which two events cause a router to advertise a connected network to OSPF neighbors? (Choose two.)
- A. When an OSPF adjacency is established.
- B. When a static route to the 224.0.0.5 address is created.
- C. When an interface has the OSPF passive option enabled.
- D. When a static route to the 224.0.0.6 address is created.
Answer: A,B
Explanation:
A is correct because when an OSPF adjacency is established, a router will advertise a connected network to OSPF neighbors. An OSPF adjacency is a logical relationship between two routers that agree to exchange routing information using the OSPF protocol1. To establish an OSPF adjacency, the routers must be in the same area, have compatible parameters, and exchange hello packets1. Once an OSPF adjacency is formed, the routers will exchange database description (DBD) packets, which contain summaries of their link-state databases (LSDBs)1. The LSDBs include information about the connected networks and their costs2. Therefore, when an OSPF adjacency is established, a router will advertise a connected network to OSPF neighbors through DBD packets.
D is correct because when a static route to the 224.0.0.5 address is created, a router will advertise a connected network to OSPF neighbors. The 224.0.0.5 address is the multicast address for all OSPF routers3. A static route to this address can be used to send OSPF hello packets to all OSPF neighbors on a network segment3. This can be useful when the network segment does not support multicast or when the router does not have an IP address on the segment3. When a static route to the 224.0.0.5 address is created, the router will send hello packets to this address and establish OSPF adjacencies with other routers on the segment3. As explained above, once an OSPF adjacency is formed, the router will advertise a connected network to OSPF neighbors through DBD packets.
NEW QUESTION # 27
Exhibit.
You want to verify prefix information being sent from 10.36.1.4.
Which two statements are correct about the output shown in the exhibit? (Choose two.)
- A. The output shows routes that are active and rejected by an import policy.
- B. The output shows routes that were received prior to the application of any BGP import policies.
- C. The routes displayed have traversed one or more autonomous systems.
- D. The routes displayed are being learned from an I BGP peer.
Answer: B,C
Explanation:
Explanation
The output shown in the exhibit is the result of the command "show ip bgp neighbor 10.36.1.4 received-routes", which displays all received routes (both accepted and rejected) from the specified neighbor.
Option A is correct, because the routes displayed have traversed one or more autonomous systems. This can be seen from the AS_PATH attribute, which shows the sequence of AS numbers that the route has passed through. For example, the route 10.0.0.0/8 has an AS_PATH of 65001 65002, which means that it has traversed AS 65001 and AS 65002 before reaching the local router.
Option B is correct, because the output shows routes that were received prior to the application of any BGP import policies. This can be seen from the fact that some routes have a status code of "r", which means that they are rejected by an import policy. The"received-routes" keyword shows the routes coming from a given neighbor before the inbound policy has been applied. To see the routes after the inbound policy has been applied, the "routes" keyword should be used instead.
Option C is incorrect, because the output does not show routes that are active and rejected by an import policy.
The status code of "r" means that the route is rejected by an import policy, but it does not mean that it is active. The status code of ">" means that the route is active and selected as the best path. None of the routes in the output have both ">" and "r" status codes.
Option D is incorrect, because the routes displayed are not being learned from an IBGP peer. An IBGP peer is a BGP neighbor that belongs to the same AS as the local router. The output shows that the neighbor 10.36.1.4 has a remote AS of 65001, which is different from the local AS of 65002. Therefore, the neighbor is an EBGP peer, not an IBGP peer.
NEW QUESTION # 28
What are two characteristics of RSTP alternate ports? (Choose two.)
- A. RSTP alternate ports provide an alternate lower cost path to the root bridge.
- B. RSTP alternate ports are active ports used to forward frames toward the root bridge.
- C. RSTP alternate ports provide an alternate higher cost path to the root bridge.
- D. RSTP alternate ports block traffic while receiving superior BPDUs from a neighboring switch.
Answer: C,D
Explanation:
A is correct because RSTP alternate ports block traffic while receiving superior BPDUs from a neighboring switch. An alternate port is a backup port for a root port, which means it receives better BPDUs from another bridge than the current root port1. However, an alternate port does not forward any traffic, as it is in a discarding state2. It only listens to BPDUs and waits for the root port to fail. If the root port fails, the alternate port can immediately transition to a forwarding state and become the new root port1.
C is correct because RSTP alternate ports provide an alternate higher cost path to the root bridge. An alternate port is selected based on the same criteria as the root port, which are the lowest bridge ID, the lowest path cost, the lowest sender port ID, and the lowest receiver port ID3. However, an alternate port receives a higher cost BPDU than the root port, otherwise it would be the root port itself1. Therefore, an alternate port provides an alternate higher cost path to the root bridge than the root port.
NEW QUESTION # 29
Exhibit.
What is the management IP address of the device shown in the exhibit?
- A. 172.23.11.10
- B. 128.0.0.1
- C. 10.210.20.233
- D. 172.23.12.100
Answer: D
Explanation:
Explanation
The management IP address of a device is the IP address that is used to access the device for configuration and monitoring purposes. It is usually assigned to a dedicatedmanagement interface that is separate from the data interfaces. The management interface can be accessed via SSH, Telnet, HTTP, or other protocols.
In the exhibit, the list of interfaces and their statuses shows that the management interface isme0. This interface has an admin status ofup, a protocol status ofinet, a local address of172.23.12.100/24, and a remote address ofunspecified. This means that the me0 interface is active, has an IPv4 address assigned, and is not connected to another device.
Therefore, the management IP address of the device shown in the exhibit is172.23.12.100.
References:
[Management Interfaces Overview] : [Displaying Interface Status Information]
NEW QUESTION # 30
Which statement about aggregate routes is correct?
- A. Aggregate routes are automatically generated for all of the subnets in a routing table.
- B. Aggregate routes are used for advertising summarized network prefixes.
- C. Aggregate routes can only be used for static routing but not for dynamic routing protocols.
- D. Aggregate routes are always preferred over more specific routes, even when the specific routes have a better path.
Answer: B
Explanation:
Explanation
Aggregate routes are used for advertising summarized network prefixes12. They help minimize the number of routing tables in an IP network by consolidating selected multiple routes into a single route advertisement1. This approach is in contrast to non-aggregation routing, in which every routing table contains a unique entry for each route1.
Therefore, option D is correct. Options A, B, and C are not correct because:
Aggregate routes can be used with both static routing and dynamic routing protocols1.
Aggregate routes are not automatically generated for all of the subnets in a routing table. They need to be manually configured1.
Aggregate routes are not always preferred over more specific routes. The route selection process in Junos OS considers several factors, including route preference and metric, before determining the active route1.
NEW QUESTION # 31
You are an operator for a network running 1S-IS. Two routers are failing to form an adjacency. What are two reasons for this problem? (Choose two.)
- A. There is a mismatched area ID between the L2 routers.
- B. There are mismatched router IDs on the L2 routers.
- C. There is no configured ISO address on any IS-IS interface.
- D. The family iso configuration is missing from the adjacency interface.
Answer: C,D
Explanation:
Explanation
The two reasons for the failure to form an adjacency in a network running IS-IS could be:
B: There is no configured ISO address on any IS-IS interface. IS-IS requires each router interface to have an ISO address configured. Without this address, the routers cannot form an adjacency1.
D: The family iso configuration is missing from the adjacency interface. The 'family iso' configuration is essential for IS-IS to function correctly. If this configuration is missing from the adjacency interface, it could prevent the formation of an adjacency1.
These explanations are based on the Enterprise Routing and Switching Specialist (JNCIS-ENT) documents and learning resources available at Juniper Networks23.
NEW QUESTION # 32
Which three protocols support BFD? (Choose three.)
- A. OSPF
- B. RSTP
- C. LACP
- D. FTP
- E. BGP
Answer: A,C,E
Explanation:
Explanation
BFD is a protocol that can be used to quickly detect failures in the forwarding path between two adjacent routers or switches. BFD can be integrated with various routing protocols and link aggregation protocols to provide faster convergence and fault recovery.
According to the Juniper Networks documentation, the following protocols support BFD on Junos OS devices1:
BGP: BFD can be used to monitor the connectivity between BGP peers and trigger a session reset if a failure is detected. BFD can be configured for both internal and external BGP sessions, as well as for IPv4 and IPv6 address families2.
OSPF: BFD can be used to monitor the connectivity between OSPF neighbors and trigger a state change if a failure is detected. BFD can be configured for both OSPFv2 and OSPFv3 protocols, as well as for point-to-point and broadcast network types3.
LACP: BFD can be used to monitor the connectivity between LACP members and trigger a link state change if a failure is detected. BFD can be configured for both active and passive LACP modes, as well as for static and dynamic LAGs4.
Other protocols that support BFD on Junos OS devices are:
IS-IS: BFD can be used to monitor the connectivity between IS-IS neighbors and trigger a state change if a failure is detected. BFD can be configured for both level 1 and level 2 IS-IS adjacencies, as well as for point-to-point and broadcast network types.
RIP: BFD can be used to monitor the connectivity between RIP neighbors and trigger a route update if a failure is detected. BFD can be configured for both RIP version 1 and version 2 protocols, as well as for IPv4 and IPv6 address families.
VRRP: BFD can be used to monitor the connectivity between VRRP routers and trigger a priority change if a failure is detected. BFD can be configured for both VRRP version 2 and version 3 protocols, as well as for IPv4 and IPv6 address families.
The protocols that do not support BFD on Junos OS devices are:
RSTP: RSTP is a spanning tree protocol that provides loop prevention and rapid convergence in layer 2 networks. RSTP does not use BFD to detect link failures, but relies on its own hello mechanism that sends BPDU packets every 2 seconds by default.
FTP: FTP is an application layer protocol that is used to transfer files between hosts over a TCP connection. FTP does not use BFD to detect connection failures, but relies on TCP's own retransmission and timeout mechanisms.
References:
1: [Configuring Bidirectional Forwarding Detection] 2: [Configuring Bidirectional Forwarding Detection for BGP] 3: [Configuring Bidirectional Forwarding Detection for OSPF] 4: [Configuring Bidirectional Forwarding Detection for Link Aggregation Control Protocol] : [Configuring Bidirectional Forwarding Detection for IS-IS] : [Configuring Bidirectional Forwarding Detection for RIP] : [Configuring Bidirectional Forwarding Detection for VRRP] : [Understanding Rapid Spanning Tree Protocol] : [Understanding FTP]
NEW QUESTION # 33
Exhibit.
Why is this OSPF adjacency remaining in this state?
- A. An area ID mismatch exists between the OSPF neighbors
- B. An MTU mismatch exists between the OSPF neighbors.
- C. A hello interval mismatch exists between the OSPF neighbors.
- D. A subnet mask mismatch exists between the OSPF neighbors.
Answer: B
Explanation:
The exhibit shows the output of the command , which displays information about the OSPF neighbors on a router1.
The output shows that the OSPF neighbor with the address 172.26.1.1 and the interface ge-0/0/3.0 is in the Exstart state1.
The Exstart state is the fourth state in the OSPF neighbor formation process, after Down, Init, and
2-Way states2. In this state, the OSPF neighbors establish a master-slave relationship and exchange database description (DBD) packets, which contain summaries of their link-state databases2.
The most common reason for OSPF neighbors to be stuck in the Exstart state is an MTU mismatch between the interfaces3. MTU stands for maximum transmission unit, which is the largest size of a packet that can be transmitted on a network segment4. If the MTU values of two OSPF neighbors are different, theymay not be able to exchange DBD packets successfully, as some packets may be dropped or fragmented due to their size exceeding the MTU limit3.
To solve this problem, you need to ensure that the MTU values of both OSPF neighbors are the same or compatible. You can use the command show interfaces to display the MTU value of an interface5. You can also use the command ping with the do-not-fragment option to test the MTU size between two routers. You can change the MTU value of an interface by using the command set interfaces interface-name mtu mtu-value in configuration mode5.
NEW QUESTION # 34
Which two statements about redundant trunk groups on EX Series switches are correct? (Choose two.)
- A. Layer 2 control traffic is permitted on the secondary link.
- B. If the active link fails, then the secondary link automatically takes over.
- C. Redundant trunk groups load balance traffic across two designated uplink interfaces.
- D. Redundant trunk groups use spanning tree to provide loop-free redundant uplinks.
Answer: A,B
Explanation:
C is correct because Layer 2 control traffic is permitted on the secondary link of a redundant trunk group (RTG) on EX Series switches. Layer 2 control traffic includes protocols such as LLDP, LACP, and STP, which are used to exchange information and coordinate actions between switches1. According to the Juniper Networks documentation2, Layer 2 control traffic is allowed to pass through both the active and the secondary links of an RTG, but data traffic is only forwarded through the active link. This allows the switches to maintain their Layer 2 adjacencies and monitor the link status on both links.
D is correct because if the active link fails, then the secondary link automatically takes over in an RTG on EX Series switches. An RTG consists of two trunk links: an active or primary link, and a secondary or backup link2. The active link is used to forward data traffic, while the secondary link is in standby mode. If the active link fails or becomes unavailable, the secondary link immediately transitions to a forwarding state and takes over the data traffic without waiting for normal STP convergence2. This provides fast recovery and redundancy for the network.
NEW QUESTION # 35
Exhibit.
You want to enable redundancy for the EBGP peering between the two routers shown in the exhibit. Which three actions will you perform in this scenario? (Choose three.)
- A. Configure an MD5 peer authentication.
- B. Configure a cluster ID.
- C. Configure BGP multihop.
- D. Configure routes for the peer loopback interface IP addresses.
- E. Configure loopback interface peering.
Answer: C,D,E
Explanation:
A is correct because you need to configure BGP multihop to enable redundancy for the EBGP peering between the two routers. BGP multihop is a feature that allows BGP peers to establish a session over multiple hops, instead of requiring them to be directly connected1. By default, EBGP peers use a time-to-live (TTL) value of 1 for their packets, which means that they can only reach adjacent neighbors1. However, if you configure BGP multihop with a higher TTL value, you can allow EBGP peers to communicate over multiple routers in between1. This can provide redundancy in case of a link failure or a router failure between the EBGP peers.
B is correct because you need to configure loopback interface peering to enable redundancy for the EBGP peering between the two routers. Loopback interface peering is a technique that uses loopback interfaces as the source and destination addresses for BGP sessions, instead of physical interfaces2. Loopback interfaces are virtual interfaces that are always up andreachable as long as the router is operational2. By using loopback interface peering, you can avoid the dependency on a single physical interface or link for the BGP session, and use multiple paths to reach the loopback address of the peer2. This can provide redundancy and load balancing for the EBGP peering.
C is correct because you need to configure routes for the peer loopback interface IP addresses to enable redundancy for the EBGP peering between the two routers. Routes for the peer loopback interface IP addresses are necessary to ensure that the routers can reach each other's loopback addresses over multiple hops2. You can use static routes or dynamic routing protocols to advertise and learn the routes for the peer loopback interface IP addresses2. Without these routes, the routers will not be able to establish or maintain the BGP session using their loopback interfaces.
NEW QUESTION # 36
Which statement is correct about the storm control feature?
- A. The storm control feature requires a special license on EX Series switches.
- B. The storm control configuration only applies to traffic being sent between the forwarding and control plane.
- C. The storm control feature is enabled in the factory-default configuration on EX Series switches.
- D. The storm control feature is not supported on aggregate Ethernet interfaces.
Answer: C
Explanation:
Option A is correct. The storm control feature is enabled in the factory-default configuration on EX Series switches12. On EX2200, EX3200, EX3300, EX4200, and EX6200 switches, the factory default configuration enables storm control for broadcast and unknown unicast traffic on all switch interfaces2. On EX4300 switches, the factory default configuration enables storm control on all Layer 2 switch interfaces1.
Option B is incorrect. The storm control feature does not require a special license on EX Series switches34.
Option C is incorrect. There's no information available that suggests the storm control feature is not supported on aggregate Ethernet interfaces.
Option D is incorrect. The storm control configuration applies to traffic at the ingress of an interface5, not just between the forwarding and control plane.
NEW QUESTION # 37
You want to use filter-based forwarding (FBF) on your Internet peering router to load-balance traffic to two directly connected ISPs based on the source address.
Which two statements are correct in this scenario? (Choose two.)
- A. RIB groups are used to copy routes from the inet. o routing table.
- B. FBF uses the no-forwarding routing instance type.
- C. RIB groups are used to hide routes in the inet. 0 routing table.
- D. FBF uses the forwarding routing instance type.
Answer: A,D
Explanation:
Option B is correct. Filter-based forwarding (FBF), also known as Policy Based Routing (PBR), uses the forwarding routing instance type12.
Option C is correct. Routing Information Base (RIB) groups are used to copy routes from one routing table to another34. In the context of FBF, RIB groups can be used to copy routes from the inet.0 routing table34.
Option A is incorrect. FBF does not use the no-forwarding routing instance type15.
Option D is incorrect. RIB groups are not used to hide routes in the inet.0 routing table34. They are used to share or copy routes between different routing tables34.
NEW QUESTION # 38
Two routers share the same highest priority and start time.
- A. The router with the highest router ID becomes the DR
- B. In this situation, what is evaluated next when determining the designated router? The router with the lowest router ID become the DR.
- C. The routers perform another DR election.
- D. The router with the highest MAC address become the DR
Answer: A
Explanation:
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:
The router with the highest OSPF priority becomes the DR. The default priority is 1, and a priority of 0 means the router will not participate in the election.
If there is a tie in priority, the router with the highest router ID becomes the DR. The router ID is a 32-bit number that uniquely identifies a router in an OSPF domain. It can be manually configured or automatically derived from the highest IP address of a loopback interface or a physical interface.
If there is a tie in router ID, the router that was first to become an OSPF neighbor becomes the DR.
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.
NEW QUESTION # 39
......
Updated PDF (New 2025) Actual Juniper JN0-351 Exam Questions: https://crucialexams.lead1pass.com/Juniper/JN0-351-practice-exam-dumps.html