Last Modified: Oct 16, 2026
Affected Product(s):
BIG-IP LTM
Fixed In:
17.5.1.10
Opened: Jul 14, 2026 Severity: 5-Cosmetic
After an HA cluster upgrade, a configuration sync from a member running an earlier BIG-IP version can copy the legacy f5hubblelcdadmin user entry to the upgraded member’s /config/bigip_user.conf. Configuration validation or save then fails with: The requested user (f5hubblelcdadmin) was not found.
Configuration validation and save operations fail on the upgraded member. If the invalid entry remains in the configuration, an MCPD reload or reboot may fail to load the configuration from text files, potentially leaving the BIG-IP tenant in a configuration error state. This can also affect device trust and configuration synchronization health
- An HA cluster is being upgraded - One member is upgraded to BIG-IP 17.5.1.6 or later while another member remains on an earlier version - A configuration sync is initiated from the older-version member to the upgraded member - The sync transfers the f5hubblelcdadmin entry into /config/bigip_user.conf - The upgraded member subsequently validates, saves, reloads, or reboots using the affected configuration
Do not synchronize configurations between HA members running different BIG-IP versions during an upgrade. Complete the upgrade on all cluster members according to K80173021, and verify that all members are running the same version before performing configuration synchronization If the invalid f5hubblelcdadmin entry is already present, remove the stale entry from /config/bigip_user.conf using the applicable F5 Support procedure, then revalidate the configuration
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