Last Modified: May 05, 2026
Affected Product(s):
BIG-IP All
Fixed In:
17.5.1.6
Opened: Mar 25, 2026 Severity: 2-Critical
Reloading config from a higher version of F5OS 2.0.0 fails when software is rolled back to a lower version, like 1.8.3. Reports an error indicating qinq is not supported, like below 01071bd8:3: The tag-mode for requested member 1.1 has to be 'none' on platforms that do not support QinQ. Unexpected Error: Loading configuration process failed.
Config reload fails and need to fix the config manually to set net vlan <vlan-name>{ dag-adjustment none fwd-mode l3 if-index 224 interfaces { x.y{ tag-mode service tagged } } tag <value> } tag-mode from "service" to "none".
Tenant version is 21.1.0 or above, and F5OS platform software running F5OS 2.0.0 or above is rolled back to a version below 2.0.0. This is seen with only r2k and r4k platforms.
Change the VLAN configuration to set "tag-mode service" to " tag-mode none". Use the BIG-IP software that fixes this problem.
When QinQ is not supported, force the tag-mode to none.