Pass the Juniper JNCIS-ENT JN0-351 Questions and answers with CertsForce

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  commands 1 2 .

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) instance 1 .  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 traffic 1 .

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_junos 1 .

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 traffic 1 .

B  is correct because the loops do not exist is one of the conditions that are verified by the receiving router to ensure that the received BGP route is valid.  A loop in BGP means that a route has been advertised by the same AS more than once, which can cause routing instability and inefficiency 1 .  To prevent loops, BGP uses the AS-path attribute, which lists the AS numbers that a route has traversed from the origin to the destination 2 .  The receiving router checks the AS-path attribute of the received route and discards it if it finds its own AS number in the list 2 . This way, BGP avoids accepting routes that contain loops.

C  is correct because the next hop is reachable is one of the conditions that are verified by the receiving router to ensure that the received BGP route is valid.  The next hop is the IP address of the next router that is used to forward packets to the destination network 3 .  The receiving router checks the next hop attribute of the received route and verifies that it has a valid route to reach it 3 .  If the next hop is not reachable, the received route is not usable and is rejected by the receiving router 3 . This way, BGP ensures that only feasible routes are accepted.

The feature that enables an interface on an EX Series switch to receive both untagged traffic (from the computer) and tagged traffic (from the IP phone) is the  voice VLAN 1 2 .

The voice VLAN feature in EX-series switches enables access ports to accept both data (untagged) and voice (tagged) traffic and separate that traffic into different VLANs 1 2 .  This allows the switch to differentiate between voice and data traffic, ensuring that voice traffic can be treated with a higher priority 1 2 . Therefore, option D is correct.

Junos devices support various types of tunnels for different purposes 1 2 .

Option B is correct.  Generic Routing Encapsulation (GRE) is a tunneling protocol that can encapsulate a wide variety of network layer protocols inside virtual point-to-point links over an Internet Protocol network 1 .  Junos devices support GRE tunnels 1 .

Option D is correct.  IPsec (Internet Protocol Security) is a protocol suite for securing Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session 1 .  Junos devices support IPsec tunnels 1 .

Option A is incorrect. Spanning Tree Protocol (STP) is not a type of tunnel.  It’s a network protocol designed to prevent loops in a bridged Ethernet local area network 2 .

Option C is incorrect.  While Junos devices do support IP-IP (also known as IP tunneling), it’s not supported on all Junos devices 1 .

A  is correct because you can deploy only stateless firewall filters on an EX Series switch.  A stateless firewall filter is a filter that evaluates each packet individually based on the header information, such as source and destination addresses, protocol, and port numbers 1 .  A stateless firewall filter does not keep track of the state or context of a packet flow, such as the sequence number, flags, or session information 1 .  EX Series switches support only stateless firewall filters, which are also called access control lists (ACLs) or packet filters 2 .

C  is correct because you can apply firewall filters to both Layer 2 and Layer 3 traffic on an EX Series switch.  Layer 2 traffic is traffic that is switched within a VLAN or a bridge domain, while Layer 3 traffic is traffic that is routed between VLANs or networks 3 .  EX Series switches support three types of firewall filters: port (Layer 2) firewall filters, VLAN firewall filters, and router (Layer 3) firewall filters 4 . You can apply these filters to different interfaces and directions to control the traffic entering or exiting the switch.

B  is correct because duplex and speed settings are required to match on both participating devices.  According to the Juniper Networks documentation 1 , all the interfaces in a LAG must have the same speed and be in full-duplex mode. This ensures that the LAG can operate as a single logical link without any performance or compatibility issues.

C  is correct because member links are not required to be contiguous ports.  According to the Juniper Networks documentation 2 , you can group any Ethernet interfaces on a switch into a LAG, regardless of their physical location or slot number. This provides flexibility and scalability for configuring LAGs on switches.

The exhibit shows the output of the command  show vlans brief , which displays brief information about VLANs and their associated interfaces 1 .

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 traffic 1 .  This can be verified by the command  show interfaces terse , which displays the status of the interfaces 2 .