Newly Released Juniper JN0-637 Exam PDF

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Question 28

Your IPsec tunnel is configured with multiple security associations (SAs). Your SRX Series device supports the CoS-based IPsec VPNs with multiple IPsec SAs feature. You are asked to configure CoS for this tunnel.

Which two statements are true in this scenario? (Choose two.)

Options:

The local and remote gateways do not need the forwarding classes to be defined in the same order.

A maximum of four forwarding classes can be configured for a VPN with the multi-sa forwarding-classes statement.

The local and remote gateways must have the forwarding classes defined in the same order.

A maximum of eight forwarding classes can be configured for a VPN with the multi-sa forwarding-classes statement.

Question 29

You have a multinode HA default mode deployment and the ICL is down.

In this scenario, what are two ways that the SRX Series devices verify the activeness of their peers? (Choose two.)

Options:

Custom IP addresses may be configured for the activeness probe.

Fabric link heartbeats are used to verify the activeness of the peers.

Each peer sends a probe with the virtual IP address as the destination IP address.

Each peer sends a probe with the virtual IP address as the source IP address and the upstream router as the destination IP address.

Answer:

A, D

Explanation:

Comprehensive Detailed Step-by-Step Explanation with All Juniper Security References

Understanding the Scenario:

Multinode HA Default Mode Deployment:

In a chassis cluster, two SRX devices operate together to provide high availability.

ICL (Inter-Cluster Link) is Down:

The control and fabric links between the nodes are not operational.

Objective:

Determine how the SRX devices verify each other's activeness without the ICL.

Option A: Custom IP addresses may be configured for the activeness probe.

Explanation:

When the control link is down, SRX devices use an ICMP ping-based activeness probe to check the peer's status.

Custom IP addresses can be configured as probe targets to verify the peer's activeness.

[Reference:, "You can configure the SRX Series device to send activeness probes to a configured IP address to verify the peer's state when the control link is down.", Source: Juniper Networks Documentation - Control Link Failure Detection, Option D: Each peer sends a probe with the virtual IP address as the source IP address and the upstream router as the destination IP address., Explanation:, The SRX devices send ICMP probes to an upstream device using the redundancy group's virtual IP address as the source., This helps determine if the peer node is still active by verifying network reachability., Reference:, "When the control link fails, each node sends ICMP pings to the configured probe addresses using the redundancy group's virtual IP address as the source.", Source: Juniper Networks Documentation - Chassis Cluster Control Link Failure, Why Options B and C are Incorrect:, Option B: Fabric link heartbeats cannot be used because the ICL (which includes the fabric link) is down., Option C: Probes are sent to upstream devices, not using the virtual IP address as the destination., Conclusion:, The correct options are A and D because they accurately describe how SRX devices verify activeness without the ICL., ]

Question 30

You are deploying OSPF over IPsec with an SRX Series device and third-party device using GRE.

Which two statements are correct? (Choose two.)

Options:

The GRE interface should use lo0 as endpoints.

The OSPF protocol must be enabled under the VPN zone.

Overlapping addresses are allowed between remote networks.

The GRE interface must be configured under the OSPF protocol.

Answer:

A, D

Explanation:

Comprehensive Detailed Step-by-Step Explanation with All Juniper Security References

Understanding the Scenario:

Objective: Deploy OSPF over IPsec between an SRX Series device and a third-party device using GRE tunnels.

Components Involved:

GRE (Generic Routing Encapsulation): Encapsulates packets to allow routing protocols like OSPF to run over IPsec tunnels.

IPsec: Provides security for the GRE tunnels.

OSPF: Dynamic routing protocol used over the GRE tunnel.

Option A: The GRE interface should use lo0 as endpoints.

Explanation:

Using the loopback interface (lo0) as the source and destination endpoints for GRE tunnels is a common best practice.

Advantages:

Stability: Loopback interfaces are always up, ensuring the GRE tunnel remains operational even if physical interfaces fail.

Reachability: Provides consistent endpoint IP addresses for GRE tunnels.

Configuration:

Assign IP addresses to lo0 interfaces on both devices.

Configure GRE tunnels to use these lo0 IP addresses as source and destination.

[Reference:, Juniper Networks Documentation:, "Using loopback interfaces as GRE tunnel endpoints ensures stability and consistent reachability for routing protocols over GRE tunnels.", Source: Configuring GRE Tunnels, Option D: The GRE interface must be configured under the OSPF protocol., Explanation:, To run OSPF over the GRE tunnel, the GRE interface must be included in the OSPF configuration., Configuration Steps:, Create GRE Interface:, Example: set interfaces gr-0/0/0 unit 0 tunnel source tunnel destination , Assign IP Address to GRE Interface:, Example: set interfaces gr-0/0/0 unit 0 family inet address , Include GRE Interface in OSPF:, Example: set protocols ospf area interface gr-0/0/0.0, Result:, OSPF will establish adjacencies over the GRE interface and exchange routing information., Reference:, Juniper Networks Documentation:, "To enable OSPF over GRE tunnels, you must include the GRE interfaces in the OSPF configuration.", Source: OSPF over GRE Configuration, Why Options B and C are Incorrect:, Option B: The OSPF protocol must be enabled under the VPN zone., Explanation:, Since OSPF is running over the GRE tunnel, which is encapsulated over IPsec, the OSPF packets are encapsulated within GRE and IPsec., The SRX device does not need to allow OSPF in the security policies or enable OSPF under the VPN zone for GRE-encapsulated traffic., Security Policies:, The GRE traffic (IP protocol 47) must be permitted through the security policies., OSPF runs inside the GRE tunnel and does not require additional configuration under the VPN zone., Reference:, Juniper Networks Documentation:, "When using GRE over IPsec, routing protocols run over GRE and do not require separate security policies for their control traffic.", Source: Security Policies for GRE over IPsec, Option C: Overlapping addresses are allowed between remote networks., Explanation:, Overlapping IP addresses can cause routing conflicts and are generally not recommended., In a GRE over IPsec scenario, overlapping addresses can lead to issues in routing protocol adjacency and data forwarding., Best Practice:, Ensure unique IP addressing schemes between remote networks to prevent routing issues., Reference:, Juniper Networks Documentation:, "Overlapping IP address spaces can lead to routing ambiguities and should be avoided when configuring GRE tunnels.", Source: Avoiding Overlapping IP Addresses, Conclusion:, Correct Answers: A and D, Rationale:, Option A is correct because using lo0 as endpoints for GRE provides stability and reliability., Option D is correct because the GRE interface must be included in the OSPF configuration to enable OSPF over the tunnel., ]

Question 31

Which two statements are correct about automated threat mitigation with Security Director? (Choose two.)