How to change the default boot location

Hi, 

So in System > Software Management > Boot Locations

You'll see the drives as you have noted in Image list.

You'll not the Unused boot location will have a "link" on it.
click that, it'll take you to another page, where you get the option to "Activate" the location and REBOOT!
Be warned, make sure you are in the right big-ip and you are ready for the down time / maintenance window.
So this will start the reboot process!
I've done it once when i thought i was in a different box, and rebooted something i shouldn't have!