To ensure high availability (HA) across multiple availability zones (AZs) in a cloud service provider (CSP) environment, using a load balancer with health probes is a recommended method. This setup ensures that traffic can be directed to the healthy NGFW instances across multiple availability zones. If one NGFW instance or availability zone goes down, the load balancer can redirect traffic to the available instance(s) in other zones, providing redundancy and maintaining service availability.

When implementing a new self-signed root certificate authority (CA) for SSL decryption on a Palo Alto Networks firewall, the subordinate CA certificate (which is generated by the firewall) must be imported into the trust stores of all client devices. This ensures that client devices trust the firewall as a valid certificate authority, enabling the firewall to decrypt and re-encrypt SSL traffic.

Importing the subordinate CA certificate into the client devices' trust stores is necessary for those devices to trust the new self-signed root CA and properly handle SSL decryption traffic.

In the context of virtual systems (VSYS) on a Palo Alto Networks firewall, the external zone is typically associated with specific interfaces within a VSYS. Zones are fundamental security objects used to define traffic flow between interfaces, and the external zone would be used for interfaces that connect to external networks.

An external zone is associated with an interface within a VSYS of the firewall. This ensures that traffic from specific interfaces can be classified as belonging to the external zone, allowing the firewall to apply appropriate security policies.

The external zone is indeed a security object that is specific to a given VSYS, as each VSYS can have its own set of zones that are isolated from others.

Local firewall rules are evaluated after Panorama pre-rules (those applied before the firewall’s local policies) and before Panorama post-rules (those applied after the firewall’s local policies). This ensures that the local firewall rules do not override the central Panorama policy and are only applied in the appropriate order within the policy evaluation sequence.

In a High Availability (HA) active/passive pair configuration, when setting up an Aggregate Ethernet (AE) interface, enabling the "Enable in HA Passive State" option allows the interface to participate in LACP (Link Aggregation Control Protocol) even when the system is in the passive state. This ensures that the pre-negotiation of the LACP link occurs, allowing the link aggregation to be ready as soon as the firewall becomes active.

When integrating Kubernetes with Palo Alto Networks NGFWs, the CN-Series firewalls are specifically designed to secure traffic between microservices in containerized environments. These firewalls provide advanced security features like Application Identification (App-ID), URL filtering, and Threat Prevention to secure communication between containers and microservices within a Kubernetes environment.

Terraform is an Infrastructure-as-Code (IaC) tool that automates the provisioning and management of infrastructure resources, including Palo Alto Networks Next-Generation Firewalls (NGFWs). By using Terraform configuration files, administrators can define and deploy NGFW instances across cloud environments (such as AWS, Azure, and GCP) efficiently and consistently.

Terraform enables:

Automated firewall deployment in cloud environments.

Configuration of security policies and networking settings in a declarative manner.

Scalability and repeatability, reducing manual intervention in firewall provisioning.

In this scenario, the customer requires that users do not directly access websites and that a security device (the firewall) manages the connection, while also ensuring that there is authentication back to the Active Directory (AD) servers for all sessions. The explicit proxy with Kerberos authentication is the best solution because:

The explicit proxy allows the firewall to intercept user web traffic and manage the connections on behalf of users.

Kerberos authentication ensures that the user’s identity is validated against the Active Directory servers before the session is allowed, fulfilling the authentication requirement.

To begin sending logs to Strata Logging Service while continuing to forward them to Panorama log collectors, the necessary configuration is to enable Cloud Logging. This option is configured in the Cloud Logging section under Device → Setup → Management in the appropriate templates. Once enabled, this ensures that logs are directed both to the Strata Logging Service (cloud) and to the Panorama log collectors.

When configuring link monitoring for high availability (HA) on a Palo Alto Networks NGFW, the following interface types are supported:

Virtual Wire: Used when you have a transparent mode firewall deployment, where the firewall operates at Layer 2 to monitor traffic between two network segments.

Layer 2: Also used in transparent mode, where the firewall operates as a Layer 2 device and can be configured for link monitoring.

Layer 3: Used in routed mode, where the firewall is involved in routing traffic and can also be configured to monitor links.

When configuring a new security zone on a Palo Alto Networks firewall, the two valid zone types are:

Tunnel: A Tunnel zone is used for traffic that is associated with a VPN tunnel, such as IPSec tunnels. Traffic passing through a tunnel interface is classified into this zone.

Virtual Wire: A Virtual Wire zone is used when a firewall operates in transparent mode (also known as Layer 2 mode). In this configuration, the firewall can inspect traffic without modifying the IP address structure of the network.