The earliest recollection of this bug is traced back to PAN-OS 8.1.13 - January 09, 2024. This bug is fixed in PAN-OS versions 8.1.13. Fixed an issue for Cloud/VM platforms where the tunnels between the log collectors did not come up when a public IP was used for the log collectors in an environment with a Panorama management server and two or more log collectors. For more information: https://docs.paloaltonetworks.com/pan-os/8-1/pan-os-release-notes/pan-os-8-1-addressed-issues/pan-os-8-1-13-addressed-issues