Forum Discussion

Cirrus

Jul 02, 2025

Solved

Local login failed to access gui

Hi i have an remote authentication using active directory, i tried to access gui and sah used local user and failed, fallback authentication is enable and fallback user is true on log secure fall...

application delivery

VGF5
Jul 02, 2025
FYI
F5 will not fallback to local authentication just because the user is missing in AD. Fallback to local only happens if the remote server is completely unreachable (network down, server offline, etc.), not if the server responds with "user not found" or "invalid password."

VGF5

Cumulonimbus

Jul 02, 2025

Hi Anzine321

When you have remote authentication (like Active Directory) set up on Classic BIG-IP, the system will only use local accounts (fallback) if the remote server is completely unreachable (for example, if the AD server is down or the network is disconnected). If the remote server is up and just rejects your login, fallback to local does NOT happen—even if you enabled fallback in the settings. That’s why you see “fallback: false” in your logs.

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