Get Juniper JN0-637 Exam Practice Questions - Real and Updated

Answer : C

Persistent NAT with target host allows external hosts to establish connections only when the internal device initiates a session first, ideal for specific interactive applications. Refer to Juniper Persistent NAT Documentation.

The scenario requires that external hosts be able to initiate a connection only if the internal device has already initiated a connection. The correct solution is Persistent NAT with target host, which ensures that a specific external host can initiate new connections back to the internal device, but only after the internal device has established a session first.

Persistent NAT with Target Host (Answer C): This allows the internal device to initiate a connection, and once established, the specified external host can also initiate new connections to the internal device on the same NAT mapping.

Example Configuration:

bash

set security nat source persistent-nat permit target-host-port

This solution is appropriate when controlled bidirectional communication is required based on an internal-initiated connection.

Answer : A, C

When Ethernet interfaces are configured as Layer 2 and added to the same VLAN without being assigned to a security zone, they will not forward traffic by default. Additionally, because they are operating in a pure Layer 2 switching mode, they lack the capability to enforce stateful security policies. For further details, refer to Juniper Ethernet Switching Layer 2 Documentation.

Explanation of Answer A (Unable to Apply Stateful Security Features):

When two interfaces are configured as Layer 2 interfaces and belong to the same VLAN but are not assigned to any security zone, traffic switched between them is handled purely at Layer 2. Stateful security features, such as firewall policies, are applied at Layer 3, so traffic between these interfaces will not undergo any stateful inspection or firewalling by default.

Explanation of Answer C (Interfaces Will Not Forward Traffic):

In Junos, Layer 2 interfaces must be added to a security zone to allow traffic forwarding. Since the interfaces in this scenario are not part of a security zone, they will not forward traffic by default until assigned to a zone. This is a security measure to prevent unintended forwarding of traffic.

Juniper Security Reference:

Layer 2 Interface Configuration: Layer 2 interfaces must be properly assigned to security zones to enable traffic forwarding and apply security policies. Reference: Juniper Networks Layer 2 Interface Documentation.

Answer : A, B

The interfaces are active and respond to ARP for virtual IP as long as the node is the primary or active node in the SRG group. This ensures high availability and proper traffic forwarding. For information, refer to Juniper SRX HA Documentation.

The exhibit shows information about a chassis cluster and its services redundancy group (SRG1). Let's analyze the relevant details:

Explanation of Answer B (Backup Node for SRG1):

The exhibit indicates that this SRX device is in the backup role for SRG1. The status: BACKUP field confirms that this device is currently in a standby role and is not the active node for the services redundancy group.

Explanation of Answer A (Interfaces Not Active):

Since the device is in the backup role, the interfaces ge-0/0/3.0 and ge-0/0/4.0 will not respond to ARP requests for the virtual IP's MAC address. Only the active node's interfaces respond to ARP requests in a chassis cluster configuration.

Juniper Security Reference:

Chassis Cluster Redundancy Overview: In a chassis cluster, the backup node does not respond to ARP requests for the virtual IP. Only the active node handles such requests to ensure seamless traffic forwarding. Reference: Juniper Chassis Cluster Documentation.

Answer : D

Answer : A, D