Bug ID 2228901: BIG-IQ Upgrade to 8.4.1 Breaks Single-NIC Deployments, Resulting in UI Access Loss

Last Modified: Aug 25, 2026

Affected Product(s):
BIG-IQ Platform(all modules)

Fixed In:
8.4.2

Opened: Feb 25, 2026

Severity: 2-Critical

Symptoms

After upgrading BIG-IQ CM or DCD with a single network interface from version 8.4.0 to 8.4.1, the management user interface becomes inaccessible on the default port 443. During the post-upgrade reboot, the system automatically reconfigures itself into single-NIC mode, changing the HTTPS port to 8443 and creating a self IP configuration called self_1nic.

Impact

-- Management UI becomes inaccessible at the expected port 443 (port changes to 8443) -- Production systems require manual intervention to restore functionality

Conditions

This issue occurs when ALL of the following conditions are met: -- BIG-IQ system (CM or DCD) has only one network interface (single-NIC configuration) -- Upgrading from BIG-IQ version 8.4.0 to version 8.4.1 -- The system database variable provision.1nic is set to a non-forced value ("enable" or "disable") before upgrade

Workaround

Force-disable single-NIC auto-detection before initiating the upgrade: tmsh modify sys db provision.1nic value forced_disable

Fix Information

The upgrade process now preserves the provision.1nic setting, preventing incorrect reconfiguration of single-NIC systems. Web UI and device discovery/import function as expected after upgrade.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips