The switchboot utility is the standard command-line tool for managing BIG-IP boot locations from the bash shell. The command switchboot -b HD1.2 sets the specified volume, HD1.2, as the active location for the next system boot. This action modifies the boot configuration but does not immediately restart the device. A subsequent reboot command is required to initiate the restart process, which will then load the newly designated active volume, HD1.2, containing version 13.1.0.6.

A. The tmsh reboot command does not accept a volume name as an argument; its syntax is simply tmsh reboot.

C. The correct flag to specify a boot volume with the switchboot utility is -b, not -I.

D. The switchboot utility is a bash shell command, not a tmsh module. The syntax tmsh switchboot is invalid.

1. F5 Networks Knowledge Base, K16461: Manually activating a new boot location.

Section: "Changing the active boot location from the command line"

Content: This document explicitly states: "To change the active boot location from the command line, you can use the switchboot utility... For example, to switch the active boot location to HD1.2, type the following command: switchboot -b HD1.2". It further instructs to "reboot the system by typing the following command: reboot". This directly validates the sequence in the correct answer.

2. F5 BIG-IP TMOS: Command Line Interface Guide, Version 15.1.0.

Section: "reboot"

Content: The guide details the tmsh reboot command syntax, which does not include an option to specify a boot volume directly (e.g., tmsh reboot HD1.2). It does, however, document the tmsh reboot volume command, which performs both actions in one step, but this specific command is not presented as an option in the question. This confirms that option A is syntactically incorrect.

3. F5 BIG-IP Systems: Getting Started, Version 15.1.0.

Chapter: "Maintaining the BIG-IP System" -> Section: "Managing software images"

Content: This guide describes the process of managing software volumes. While often focusing on the GUI, it references the underlying command-line tools for advanced administration, confirming that switchboot is the designated utility for this task outside of tmsh or the GUI.