Bug ID 674455: Serial console baud rate setting lost after running 'tmidiag -r' in Maintenance OS

Last Modified: May 14, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP All(all modules)

Known Affected Versions:
12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3,,,,, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0,,,,,,,

Fixed In:
14.1.0, 14.0.0,,

Opened: Jul 18, 2017
Severity: 3-Major


When booted into the Maintenance OS image from the grub boot menu, running tmidiag -r drops the serial console from the grub kernel line, which causes a loss of communication on the serial console after rebooting.


Serial console baud rate settings are incorrect. Uses the bios baud rate on the console.


-- Booted into Maintenance OS. -- Running the command: tmidiag -r


When booting, edit the grub kernel line to include console=ttyS0. Note: The value is "tty", an uppercase "S" character, and zero, so ttyS0.

Fix Information

tmidiag has been fixed to not strip out console=ttyS0.

Behavior Change