Path Monitoring is incorrectly displaying a status of 'up' in an Active/Active HA deployment, even when the firewall cannot reach the monitored IP address.

Path Monitoring is incorrectly displaying a status of 'up' in an Active/Active HA deployment, even when the firewall cannot reach the monitored IP address.

1787
Created On 07/22/24 17:11 PM - Last Modified 11/05/25 22:22 PM


Symptom


  • Path monitor shows as "up" even when routes to the destination IP (8.8.8.8) are removed.
  • No HA status change to Active-Secondary despite the inability to reach the monitored IP address.
  • Example scenario: Disabling the BGP peer or removing static routes on the firewall removes the default route to the destination IP but the path monitor still shows "up."
We observed that the HA state remained in active-primary mode despite the absence of routes to the destination, with the destination IP appearing as UP.
(active-primary)> show high-availability all
Path Monitoring Information:
Enabled: yes
Failure condition: any
Virtual-Router name: LR-FW
Enabled: yes
Failure condition: any
Ping Interval: 200 ms
Ping Count: 10
Destination Group: PING
Enabled: yes
Failure condition: any
Destination IP Address: 8.8.8.8: up
<===============
Configuration Synchronization:
Enabled: yes
Running Configuration: synchronized
> test advanced-routing fib-lookup ip 8.8.8.8 logical-router LR-FW

--------------------------------------------------------------------------------
runtime route lookup
--------------------------------------------------------------------------------
logical-router: LR-FW
destination: 8.8.8.8
result:
route not found <=====================

 


Environment


  • Palo Alto Firewall.
  • PAN-OS 8.1 and above.
  • High Availablity in Active-Active mode. 
  • Advanced Routing


Cause


The wrong slot is set when there is no ARP or route.

Resolution


The issue will be fixed in PAN-OS versions 11.2.5 and 11.1.5. Upgrading these versions will resolve the path monitoring malfunction in Active/Active HA deployments.

Additional Information


 

 



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