@DPWorld ,
Man you're gonna have a fun time.
Ensure that you have downloaded the following PAN-OS images. You might want to do so locally to a laptop or something you'll actually be doing the upgrade from, depending on how much free space you have on the device you might run out of space.
- 6.1.21 (Latest Maintenance release for your current release)
- 7.0.1 (Base Release image for 7.0)
- 7.0.19 (Latest Maintenance release for the 7.0 release)
- 7.1.0 (Base Image)
- 7.1.22 (Maintenance Release)
- 8.0 (Base Image)
- 8.0.16 (Latest Maintenance Release)
- 8.1 (Base Image)
- 8.1.* (Whatever your target release is in the 8.1 release)
Basic install practices remain the same, ensure you have free disk space, ensure you disable preempt, take a backup of your configuration.
You'll then perform the upgrade like so.
- 6.1.5 -> 6.1.21
- 6.1.21 -> 7.0.1
- 7.0.1 -> 7.0.19
- 7.0.19 -> 7.1.0
- 7.1.0 -> 7.1.22
- 7.1.22 -> 8.0
- 8.0 -> 8.0.16
- 8.0.16 -> 8.1
- 8.1 -> 8.1.* (Whatever target maintenance release)
You should be okay with upgrading just a single HA member through all steps before moving to the next, but you are moving through a lot of images. I would recommend that you actually break (not suspend) HA temporarily to ensure that the one you are in the middle of upgrading doesn't become active. This would envolve ensuring all cables are unplugged so that even if the device becomes "active" it isn't actually processing any traffic.
I've put this entire upgrade path on the latest recommended upgrade model which didn't really become a thing until 8.0; not knowing to model of firewall you are upgrading or your comfort in trully verifying disk space I would recommend you follow this model instead of the old model which would be fewer steps to avoid any issues.
