If you use SP flashtool to update your Sony Xperia device using the FTF firmware file, we’got some really amazing tool to share with you. Dubbed as ‘dd flasher’, it allows you to retain the root access on your Xperia while updating to the latest software. You’ll need to do some labor of course, but that’s nothing given the prize — no more waiting for root for the latest software update.
dd flasher requires you to separate the system partition from the FTF firmware file, and feed to it, which it will modify for the root access that’s already present on your Xperia using the ADB as talking tool. It would then flash the modified system partition on your phone automatically, while you do the rest of the work: flashing the FTF firmware using SP flashtool, while — it’s important! — making sure that you don’t select the system partition on flashtool, because it’s already been pushed onto phone by dd flasher in modified, rooted form.
Credit for the dd flasher root-keeper tool goes to mbc07, who has also written up a good enough guide as help, so that you’re not left guessing. Do donate the guy if oyu find his work as lifesaver!
How to Use DD Flasher tool
What you’ll need to do it is get a firmware file in .FTF format, and the flashtool, along with your already rooted Xperia device, which you want to update.
Next, you extract the FTF file to get .sin files, and then use the SIN editor tool in flashtool to extract the system.sin file to get the system.ext4 file.
Grab dd flasher, extract it, move the system.ext4 to this folder. Now, connect the phone to PC in MTP mode, make sure there is 2GB free on internal storage and then run the dd flasher tool, select internal storage as storage of choice, and let dd flasher modify the system.ext4 to instill root access and then flash it onto system partition.
» Be patient while dd flasher is doing its job — system.ext4 being a large file, it would take the tool some time to do its magic, and you might see LED light firing up all colors from the rainbow but just don’t worry, don’t think of device as dead, either. It won’t respond, but then it’s not meant to respond. Just look at computer what dd flasher has to say. When it says it’s job is finished, DO NOT turn your device on.
Instead, do this, and it’s important you do this. Plug out the USB cable, pull out battery (if it’s not removable, then use off/reset microswitch), and then place it back after a few seconds. DO NOT turn on just yet, again.
At this point, you have the system partition from the new update, with root access instilled, flashed on your phone, but you don’t have the other partitions of the update. So what do we do? We flash those other partitions as usual, using the flashtool, but there’s a catch!
Now, you need to flash the firmware, the .FTF file, on phone using the flashtool, but just make sure that you don’t select the system partition for flashing. Why, because we’ve already modified it and loaded on your phone using the dd flasher tool. Once the flashtool is done, disconnect the phone and turn it on now.
The first boot may take more time than usual, but if everything went alright, you must be rocking the latest software from the FTF file with old root access.
That’s it. Thank the developer mbc07 for this.
And let us now if you need any help with this, using the comment section below.