PA-3000 Series and PA-500 firewalls support larger capacities in PAN-OS 7.1 than in prior PAN-OS releases.
If you want to downgrade a PA-3000 Series or PA-500 firewall to an older PAN-OS release, perform Step 1 through Step 5 and Step 8 to downgrade successfully. If you want to downgrade a PA-3000 Series firewall and preserve the capacity increases gained when upgrading to PAN-OS 7.1 but you have not used the debug system arp-mac-capacity increase operational command, then perform all steps in the following procedure.
Use the following procedure to downgrade PA-3000 Series and PA-500 firewalls and preserve PA-3000 Series firewall capacity increases on downgrade.
Downgrade PA-3000 Series and PA-500 Firewalls and Preserve PA-3000 Series Firewall Capacity Increases on Downgrade
Determine the decreased number of ARP entries the older release supports. Access the Product Selection Tool and find the ARP capacity of the release to which you are downgrading.
Determine if you currently have more static ARP entries than the number supported in Step 1. In the CLI, use the clear arp all command to delete the dynamic ARP entries. Use the show arp all command to display a count of all the ARP entries. Because you just deleted the dynamic ARP entries, only the static ARP entries are counted.
Export the running configuration. Select Device > Setup > Operations > Save named configuration snapshot, enter a Name, and click OK. Export named configuration snapshot, select the name of the file you created from the drop-down, and click OK.
If your current static ARP entries (determined by Step 2) exceed the decreased number of ARP entries supported (determined by Step 1), delete enough static ARP entries to get the firewall below the downgraded capacity. Select Network > Virtual Routers > Static Routes. Select IPv4 or IPv6. Select a static route and Delete it; repeat as necessary. Click OK and Commit.
Downgrade the PAN-OS version to 7.0.1. Select Device > Software, select the 7.0.1 software image that is downloaded, and Install it.
Enable larger capacities on a PA-3050 or PA-3020 firewall. This command is available only in PAN-OS 6.1.0 and PAN-OS 7.0.1. In the CLI, use the debug system arp-mac-capacity increase operational command.
Upgrade the PAN-OS version to 7.1. Upgrade a Firewall to PAN-OS 7.1
Import the saved configuration. Select Device > Setup > Operations > Import named configuration snapshot, select the file you created in Step 3 to import, and click OK.
Downgrade the PAN-OS version to 7.0.1 again. Select Device > Software, select the 7.0.1 software image that is downloaded, and Install it.

Related Documentation