fastboot set_active command does not exist I am trying to root my Xiaom mi a2 phone. But i am stuck on changing the active partition. When i enter "fastboot set_active b" it doesnt execute the command. Instead i get a list off all available commands which doesnt contain an option to change the active partition.

Console-Output


I am following this tutorial: Tutorial
First you need the actual fastboot, e.g. 1.4.3 (from link in the other answer).
Then the correct command is:

fastboot --set-active=a


or:

fastboot --set-active=b


In the help (fastboot help) you can read in fastboot version 28.0.3:

--slot &lt;slot&gt;                          Specify slot name to be used if the
                                       device supports slots. All operations
                                       on partitions that support slots will
                                       be done on the slot specified.
                                       'all' can be given to refer to all
                                       slots.'other' can be given to refer to 
                                       a non-current slot. If this flag is not
                                       used, slotted partitions will default
                                       to the current active slot.


-a, --set-active[=&lt;slot&gt;]              Sets the active slot. If no slot is
                                       provided, this will default to the
                                       value given by --slot. If slots are
                                       not supported, this does nothing.
                                       This will run after all non-reboot 
                                       commands.