This article explains an issue where the MNHA cluster fails over from one node to another continuously.

You will notice that the active and backup roles for SRG1+ shift from node0 to node1 and vice versa continuously after every few minutes. This will cause traffic interruption as well. You can use below given command to monitor the cluster status:

user@srx>show chassis high-availability information 

When you configure BFD monitoring for upstream or downstream links in an MNHA setup, you may encounter situations where BFD sessions flap intermittently or randomly, which can trigger repeated cluster failovers. BFD Flapping is usually related to factors such as device load, link quality, or peer capabilities, and not due to any inherent limitation of SRX. In fact, BFD monitoring works normally and reliably with MNHA on SRX platforms when configured with appropriate timers and aligned to the environment’s capabilities.

You can use the following command to monitor BFD sessions:

While troubleshooting BFD-related issues, ensure that the BFD timers are configured according to the recommendations provided in the following Juniper document: BFD-Based Probing.

Note: If BFD sessions continue to flap without a clear or identifiable cause, it is recommended to contact JTAC for assistance in diagnosing and resolving the root cause.