Palo Alto

This topic provides configuration for a Palo Alto device. The configuration was validated using PAN-OS version 8.0.0.

Palo Alto experience is required.

Important

Oracle provides configuration instructions for a tested set of vendors and devices. Use the correct configuration for the vendor and software version.

If the device or software version that Oracle used to verify the configuration doesn't exactly match the device or software, you might still create the necessary configuration on the device. Consult the vendor's documentation and make any necessary changes.

If the device is from a vendor not in the list of verified vendors and devices, or if you're already familiar with configuring the device for IPSec, see the list of supported IPSec parameters and consult the vendor's documentation for help.

Oracle Cloud Infrastructure offersSite-to-Site VPN, a secure IPSec connection between your on-premises network and a virtual cloud network (VCN).

The following diagram shows a basic IPSec connection to Oracle Cloud Infrastructure with redundant tunnels. IP addresses used in this diagram are only examples.

This image summarizes the general layout of your on-premises network, VPN Connect IPSec tunnels, and VCN.

Best Practices

This section covers general best practices and considerations for using Site-to-Site VPN.

Configure All Tunnels for Every IPSec Connection

Oracle deploys two IPSec headends for connections to provide high availability for mission-critical workloads. On the Oracle side, these two headends are on different routers for redundancy purposes. We recommend configuring all available tunnels for maximum redundancy. This is a key part of the "Design for Failure" philosophy.

Have Redundant CPEs in On-Premises Network Locations

We recommend that each site that connects with IPSec to Oracle Cloud Infrastructure has redundant edge devices (also known as customer-premises equipment (CPE)). You add each CPE to the Oracle Console and create a separate IPSec connection between a dynamic routing gateway (DRG)  and each CPE. For each IPSec connection, Oracle provisions two tunnels on geographically redundant IPSec headends. For more information, see the Connectivity redundancy guide (PDF).

Routing Protocol Considerations

When you create a Site-to-Site VPN IPSec connection, it has two redundant IPSec tunnels. Oracle encourages you to configure the CPE to use both tunnels (if the CPE supports it). In the past, Oracle created IPSec connections that had up to four IPSec tunnels.

The following three routing types are available, and you select the routing type separately for each tunnel in the Site-to-Site VPN:

  • BGP dynamic routing: The available routes are learned dynamically through BGP. The DRG dynamically learns the routes from the on-premises network. On the Oracle side, the DRG advertises the VCN's subnets.
  • Static routing: When you set up the IPSec connection to the DRG, you specify the particular routes to the on-premises network that you want the VCN to know about. You also must configure the CPE device with static routes to the VCN's subnets. These routes aren't learned dynamically.
  • Policy-based routing: When you set up the IPSec connection to the DRG, you specify the particular routes to the on-premises network that you want the VCN to know about. You also must configure the CPE device with static routes to the VCN's subnets. These routes aren't learned dynamically.

For more information about routing with Site-to-Site VPN, including Oracle recommendations on how to manipulate the BGP best path selection algorithm, see Routing for Site-to-Site VPN.

Other Important CPE Configurations

Ensure that access lists on the CPE are configured correctly to not block necessary traffic from or to Oracle Cloud Infrastructure.

If you have several tunnels up simultaneously, you might experience asymmetric routing. To account for asymmetric routing, ensure that the CPE is configured to handle traffic coming from the VCN on any of the tunnels. For example, you need to disable ICMP inspection, configure TCP state bypass . For more details about the appropriate configuration, contact the CPE vendor's support. To configure routing to be symmetric, see Routing for Site-to-Site VPN.

Caveats and Limitations

This section covers general important characteristics and limitations of Site-to-Site VPN to be aware of. See Service Limits for a list of applicable limits and instructions for requesting a limit increase.

Asymmetric Routing

Oracle uses asymmetric routing across the tunnels that make up the IPSec connection. Configure firewalls with that in mind. Otherwise, ping tests or application traffic across the connection don't work reliably.

When you use several tunnels to Oracle Cloud Infrastructure, We recommend that you configure routing to deterministically route traffic through the preferred tunnel. To use one IPSec tunnel as primary and another as backup, configure more-specific routes for the primary tunnel (BGP) and less-specific routes (summary or default route) for the backup tunnel (BGP/static). Otherwise, if you advertise the same route (for example, a default route) through all tunnels, return traffic from a VCN to an on-premises network routes to any of the available tunnels. This is because Oracle uses asymmetric routing.

For specific Oracle routing recommendations about how to force symmetric routing, see Routing for Site-to-Site VPN.

Route-Based or Policy-Based Site-to-Site VPN

The IPSec protocol uses Security Associations (SAs) to decide how to encrypt packets. Within each SA, you define encryption domains to map a packet's source and destination IP address and protocol type to an entry in the SA database to define how to encrypt or decrypt a packet.

Note

Other vendors or industry documentation might use the term proxy ID, security parameter index (SPI), or traffic selector when referring to SAs or encryption domains.

There are two general methods for implementing IPSec tunnels:

  • Route-based tunnels: Also called next-hop-based tunnels. A route table lookup is performed on a packet's destination IP address. If that route's egress interface is an IPSec tunnel, the packet is encrypted and sent to the other end of the tunnel.
  • Policy-based tunnels: The packet's source and destination IP address and protocol are matched against a list of policy statements. If a match is found, the packet is encrypted based on the rules in that policy statement.

The Oracle Site-to-Site VPN headends use route-based tunnels but can work with policy-based tunnels with some caveats listed in the following sections.

If Your CPE Is Behind a NAT Device

In general, the CPE IKE identifier configured on the on-premises end of the connection must match the CPE IKE identifier that Oracle is using. By default, Oracle uses the CPE's public IP address, which you provide when you create the CPE object in the Oracle Console. However, if a CPE is behind a NAT device, the CPE IKE identifier configured on the on-premises end might be the CPE's private IP address, as shown in the following diagram.

This image shows the CPE behind a NAT device, the public and private IP addresses, and the CPE IKE identifier.
Note

Some CPE platforms don't let you change the local IKE identifier. If you can't, you must change the remote IKE ID in the Oracle Console to match the CPE's local IKE ID. You can provide the value either when you set up the IPSec connection, or later, by editing the IPSec connection. Oracle expects the value to be either an IP address or a fully qualified domain name (FQDN) such as cpe.example.com. For instructions, see Changing the CPE IKE Identifier That Oracle Uses.

CPE Configuration

Important

The configuration instructions in this section are provided by Oracle Cloud Infrastructure for this CPE. If you need support or further help, contact the CPE vendor's support directly.

The following figure shows the basic layout of the IPSec connection.

This image summarizes the general layout of the IPSec connection and tunnels.

Important Details About the Configuration Instructions

  • Commits: For PAN to activate the configuration, you must perform the commit action after any configuration change.
  • Example IP addresses: The example configuration uses IP addresses from class A 10.0.0.0/8 (RFC1918) and 198.51.100.0/24 (RFC5735). When you perform the configuration on the CPE, use the correct IP addressing plan for your networking topology.

The example configuration uses the following variables and values:

  • Inside tunnel1 interface - CPE: 198.51.100.1/30
  • Inside tunnel2 interface - CPE: 198.51.100.5/30
  • Inside tunnel1 interface - Oracle: 198.51.100.2/30
  • Inside tunnel2 interface - Oracle: 198.51.100.6/30
  • CPE ASN: 64511
  • On-premises network: 10.200.1.0/24
  • VCN CIDR block: 10.200.0.0/24
  • CPE public IP address: 10.100.0.100/24
  • Oracle VPN headend (DRG) IP address 1: 10.150.128.1/32
  • Oracle VPN headend (DRG) IP address 2: 10.150.127.1/32
  • Tunnel number 1: tunnel.1
  • Tunnel number 2: tunnel.2
  • Exit interface: ethernet1/1

About Using IKEv2

Oracle supports Internet Key Exchange version 1 (IKEv1) and version 2 (IKEv2). If you configure the IPSec connection in the Console to use IKEv2, you must configure your CPE to use only IKEv2 and related IKEv2 encryption parameters that your CPE supports. For a list of parameters that Oracle supports for IKEv1 or IKEv2, see Supported IPSec Parameters.

If you want to use IKEv2, there are special variations of some steps presented in the next section. Here is a summary of the special steps:

Configuration Process

The following process includes BGP configuration for the IPSec connection. If you instead want to use static routing, perform tasks 1–5, and then skip to CPE Configuration.

Configuring Static Routing

Use the instructions here if your CPE does not support BGP over IPSec, or you do not want to use BGP over IPSec.

In this task, you configure static routes to direct traffic through the tunnel interfaces to reach the DRG and finally the VCN hosts.

  1. Follow tasks 1–5 in the preceding section.
  2. Configure static routes:
    1. Go to Network, to Virtual Routers, to default, to Static Routes, and then click Add.
    2. For Route 1, configure the parameters as shown in the next image.

      This image shows the static route settings for route 1.
    3. For Route 2, configure the parameters as shown in the next image.

      This image shows the static route settings for route 2.
  3. (Recommended) Enable ECMP for traffic sent through the two tunnels. The metric for both routes is set to 10. Here are some important notes about enabling ECMP:

    • First check to see if your networking design allows for ECMP.
    • Enabling or disabling ECMP on an existing virtual router causes the system to restart the virtual router. The restart might cause existing sessions to be terminated.
    • This example uses the default virtual router. Use the correct virtual router for your network environment.

    To enable ECMP, go to Network, to Virtual Routers, to default, to Router Settings, to ECMP, and then select Enable.

    This image shows the ECMP settings.

Here are screenshots that show the final configuration after this task is complete:

This image shows the final configuration on the IPv4 tab after configuring static routes.
This image shows the final configuration after configuring static routes.

Changing the IKE Identifier

If the CPE is behind a NAT device with a private IP address on the exit interface that the tunnel interfaces use as the source, you must specify the public IP address of the NAT device as the local IKE ID. You can do this by setting the Local Identification value in the IKE Gateway configuration:

This image shows where to change the CPE's IKE identifier.

Verification

To verify the IPSec tunnel status:

This image shows where to verify the IPSec tunnel status.

Use this command to verify the IKE SA:

show vpn ike-sa

Use this command to verify the IPSec tunnel configuration:

show vpn tunnel name <tunnel_name>

To verify the BGP status, look for Established:

This image shows where to verify the BGP status.

To verify the BGP status from the command line:

show routing protocol bgp peer peer-name <name>

To verify that the routes are installed in the route table:

show routing route

A Monitoring service is also available from Oracle Cloud Infrastructure to actively and passively monitor cloud resources. For information about monitoring a Site-to-Site VPN, see Site-to-Site VPN Metrics.

If you have issues, see Site-to-Site VPN Troubleshooting.