When you upgrade from one PAN-OS feature release
version to a later feature release, you cannot skip the installation
of any feature release versions in the path to your target release.
In addition, the recommended upgrade path includes installing the
latest maintenance release in each release version before you install the
base image for the next feature release version. To minimize downtime
for your users, perform upgrades during non-business hours.
For
manual upgrades, you must install the base image for a feature release before
you upload and install a maintenance release image.
Determine
the upgrade path as follows:
Identify
which version is currently installed.
From Panorama, select
Panorama
Managed Devices
and check the
Software Version on the firewalls you plan to upgrade.
From the firewall, select
Device
Software
and check which version
has a check mark in the Currently Installed column.
Identify the upgrade path:
Review the known issues and changes
to default behavior in the Release Notes and upgrade/downgrade
considerations in the New Features Guide for
each release through which you pass as part of your upgrade path.
Installed PAN-OS Version
Recommended Upgrade Path to PAN-OS 9.1
9.0.x
If you are already running
a PAN-OS 9.0 release, download and install the preferred PAN-OS 9.0 maintenance
release and reboot. You can then proceed to Upgrade the Firewall to PAN-OS 9.1.