Booting the BIG-IP system in single-user mode

https://support.f5.com/kb/en-us/solutions/public/4000/100/sol4178.html


How-To

Original Publication Date: 05/16/2007
Updated Date: 04/24/2013

On certain occasions, it may be necessary to boot the BIG-IP system into single-user mode to fix operating system issues, such as filesystem or root password issues.
To boot the BIG-IP system into single-user mode, perform the following procedure:

Note: To perform the following steps, you must be local to the BIG-IP system with a console connection or using a console server.

1. Connect a terminal to the BIG-IP serial console port.
2. Reboot the BIG-IP system.While booting, the BIG-IP system displays the GRUB menu and counts down before continuing the boot process.
   
3. Before the countdown expires, use the up and down arrow keys to select the appropriate boot image.
   Note: Alternately, press SHIFT+6 (^) to arrow up, and press the v key to arrow down.
4. Press the e key to edit the boot options.
   
   A new GRUB menu screen displays.
5. Use the up and down arrow keys to select the line that begins with kernel /boot/vmlinuz.
   Note: Alternately, press SHIFT+6 (^) to arrow up and press the v key to arrow down.
6. Press the e key to edit the line.
7. Add the word single to the end of the kernel /boot/vmlinuz line, and then press the Enter key.For example:
   
   kernel /boot/vmlinuz single
   Depending on the platform, the boot command may instead appear similar to the following example:
   
   kernel (hd1,1) /boot/1/vmlinuz ro root=UUID=f6155ffc-db65-46e9-9ba6-7f842a7d06ee console==tty0 console=ttyS0 19200 panic=1 mem=384M platform = D68 quiet single
8. The previous menu screen appears, and the system shows the new boot command.
9. Press the b key to boot the system using the modified options.
10. A prompt displays.

You have now booted the system in single-user mode. When you are finished using single-user mode, type exit or reboot to return the BIG-IP system to normal operating mode.