The earliest recollection of this bug is traced back to PAN-OS 9.1.8 - July 29, 2024. This bug is fixed in PAN-OS versions 9.1.8. Fixed an issue where SNMP readings reported 0 for dataplane interface packet statistics when using PacketMMAP mode. This issue occurred because the physical port counters read from MAC addresses were reported as 0. For more information: https://docs.paloaltonetworks.com/pan-os/9-1/pan-os-release-notes/pan-os-9-1-addressed-issues/pan-os-9-1-8-addressed-issues