I hope ye all are well. We recently worked a case for a customer that had dual ISP configuration and wanted the Palo Alto Networks device to provide redundancy for the Global Protect Portal and Gateways in the event one ISP went down. We came up with a handy way of providing this using NAT rules and a loopback and I am posting this to share with the community.
There are some screenshots from the lab below. Eth1/1 & Eth1/2 represent ISP-A and ISP-B.
We popped the Global Protect Portal and Gateway on a loopback interface.
We created two NAT rules to bounce the incoming traffic whether its from ISP-A or ISP-B to the loopback address.
The system has two Virtual Routers for both ISP's. VR-A and VR-B. VR-A has the loopback interface added.
Virtual Router B has a static route to VR-A which has a route to the loopback interface with the Portal and Gateway.
This simple setup allows access to the portal and gateway from either ISP interfaces. We simulated one ISP failing and changed the A record of the portal fqdn to resolve to the other interface and the users could connect without any input or changes from the end user. There are a number of ways to automate dns integrity and failover to resolve to a different ip address if it can't resolve to another. Beyond the scope of Palo Alto. Infoblox and Route 53 can provide these features. If you just have MS server , changing the A record from one IP to another isn't a massive task.
Hope this helps few others and is nice way to provide extra layer of redundancy for networks to big to fail.
Great article @DonohoeRobert. Thank you for sharing this solution! Question: Even though the Portal and Gateway configurations point to the loopback interface and the loopback interface is assigned to the Global-Protect security zone, in Tunnel Settings in Agent in Gateway configuration, did you still have to configure a tunnel interface and choose it in here? Or did you leave 'Tunnel Mode' unchecked?
Have you tried Redundancy for this case, you have configured only one default route(0.0.0.0/0) that belongs to Ethernet 1/1.
How will another interface(Ethernet1/2 ) route the traffic if Ethernet1/1 goes down?
Network Security Engineer
Click Accept as Solution to acknowledge that the answer to your question has been provided.
The button appears next to the replies on topics you’ve started. The member who gave the solution and all future visitors to this topic will appreciate it!
These simple actions take just seconds of your time, but go a long way in showing appreciation for community members and the LIVEcommunity as a whole!
The LIVEcommunity thanks you for your participation!