Floating IP does not work on standby

Good day,

We have a strange issue on our Viprion environment.

For the CVE vulnerability we had to upgrade our software version from BIGIP-13.1.3.2-0.0.4 to BIGIP-13.1.3.4-0.0.5.

The standby hypervisor and guests was upgraded and fail over was completed.

However we found that on one of the guests one of the applications failed. (Other applications on the guest works)

It seems that the floating IP is not used in communication for the application traffic.

All other guests (five guests) on the hypervisor works without any problems

Once the software is failed back to the BIGIP-13.1.3.2-0.0.4 the application starts working when the same process is followed.

All behavior seemed to be pointing to a software bug however we performed another test by upgrading to version 15.

After the upgrade we still experienced the same issue when the standby becomes the active guest

Floating is set to traffic-group 1 on both

Configs are in sync

VLAN's are the same

If there was a configuration difference the application should also fail when running on the BIGIP-13.1.3.2-0.0.4 version

We do use route domains and there is an irule on the configuration

Because the application is configured in a partition for its route domain I do not think we need to specify a % if we single out a node in the irule

Any suggestions or has someone run into the same problem?