https://docs.paloaltonetworks.com/pan-os/11-0/pan-os-admin/user-id/deploy-user-id-in-a-large- scale-network/share-user-id-mappings-across-vsys

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.
https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-upgrade/upgrade-pan-os/upgrade-the- firewall-pan-os/determine-the-upgrade-path

https://docs.paloaltonetworks.com/panorama/10-2/panorama-admin/manage-firewalls/manage- device-groups/manage-precedence-of-inherited-objects

You can check global counters for a specific source and destination IP addresses by setting a packet filter. We recommend that you use the global counter command with a packet filter to get specific traffic outputs. These outputs will help isolate the issue between two peers.
Use the following CLI command to show when traffic is passing through the Palo Alto Networks firewall from that source to destination.
> show counter global filter packet-filter yes delta yes
Global counters:
Elapsed time since last sampling: 20.220 seconds
name value rate severity category aspect description
-------------------------------------------------------------------------------- pkt_recv 6387398 4 info packet pktproc Packets received pkt_recv_zero 370391 0 info packet pktproc Packets received from QoS 0 Etc.
https://live.paloaltonetworks.com/t5/Management-Articles/How-to-check-global-counters-for-a- specific-source-and/ta-p/65794