The earliest recollection of this bug is traced back to PAN-OS 10.2.10-h21 - December 02, 2024. This bug is fixed in PAN-OS versions 10.2.10-h21, 10.2.8-h10, 11.0.4, 11.1.3. Fixed an issue where ARP entries were unable to be completed for subinterfaces with SNAT configured. For more information: https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-release-notes/pan-os-10-2-10-known-and-addressed-issues/pan-os-10-2-10-h21-addressed-issues https://docs.paloaltonetworks.com/pan-os/10-2/pan-os-release-notes/pan-os-10-2-8-known-and-addressed-issues/pan-os-10-2-8-h10-addressed-issues https://docs.paloaltonetworks.com/pan-os/11-0/pan-os-release-notes/pan-os-11-0-4-known-and-addressed-issues/pan-os-11-0-4-addressed-issues https://docs.paloaltonetworks.com/pan-os/11-1/pan-os-release-notes/pan-os-11-1-3-known-and-addressed-issues/pan-os-11-1-3-addressed-issues