https://live.paloaltonetworks.com/t5/next-generation-firewall/upgrade-path-from-panos-9-0-17-h5-to-10-1-13-h1/m-p/592740#M3464 <P>Hello,</P> <P>I have upgraded from 9.1 to 10.2 and it have taken 5hours (including debug for a new functionality). 3 reboots were needed.</P> <P>I really advise you to check new features via release notes to be sure that you will have no impact. I strongly suggest that you opened a tac before your operation in order that if you have a problem the tac will be available straight.</P> <P><STRONG>Back up configuration and device state before every upgrade.</STRONG></P> <P><A href="https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-upgrade/upgrade-pan-os/downgrade-pan-os/downgrade-a-firewall-to-a-previous-feature-release" target="_blank" rel="noopener">https://docs.paloaltonetworks.com/pan-os/10-1/pan-os-upgrade/upgrade-pan-os/downgrade-pan-os/downgrade-a-firewall-to-a-previous-feature-release</A></P> <P>For the rolll back u may have to do 3 reboots in order to be safe : <SPAN>10.1.x---&gt;10.0.x---&gt;9.1.x</SPAN></P> <P>&nbsp;</P> <P><SPAN>FYI : "While upgrading to PAN-OS 10.1, the firewall may perform a file system integrity check (FSCK), displaying the following message: RAID log disks check in progress, please wait.<BR />The FSCK is required for the upgrade and may take an hour or more. Do not reboot or attempt to install another software release while the FSCK is in progress".&nbsp;</SPAN></P> Tue, 23 Jul 2024 08:39:59 GMT RomainSalmon 2024-07-23T08:39:59Z