Last Modified: Jul 28, 2026
Affected Product(s):
F5OS F5OS-C
Fixed In:
F5OS-C 1.8.2-HR1
Opened: Apr 21, 2026 Severity: 3-Major
Upon optic re-insertion in 4x100G mode on BX520 blades, there is an issue in MAC enable for lanes 2 to 4. For example, if port 3/2 is in 4x100G mode and the optic is hot-swapped, then the MAC will be enabled only for the first link 3/2.1 and not for 3/2.2-2.4.
The issue in MAC enable for lanes 2 to 4 will cause an issue when sending out the egress packets on lanes 2 to 4 of the port.
On a BX520 blade, the front panel port is in bifurcated mode (4x100G), and the optic is hot-swapped (removed and re-inserted).
Admin bounce of ALL interfaces will help facilitate a clean link-up. Administratively disable the 4x100G interfaces before removing the optic. Then remove and re-insert the optic. Then re-enable the interfaces.
Added a change in optic_removal part of the code such that linkscan is disabled upon optic being removed, and there are no spurious UP events for lanes 2 to 4, and make mac_enable get processed prematurely and incorrectly for them.