How to root your sony Z2?

DISCLAIMER: This is not a step by step tutorial on how to root your Z2, this post contains general information on how to root sony Z2 based on my experience
I tried to root my sony xperia z2, and spent a whole day doing it, I learned a lot, and for me at least, it was not worth it.  Read all post before rooting, it MAY HELP YOU! Thanks

I am a complete newb on rooting, and after many hours, learning from my mistakes, having a couple of bootloops, or boot stuck, soft brick, etc... I was able to root my device.


Basically I followed this tutorial:
https://www.youtube.com/watch?v=53c1FwdjxtY

which is from xda developers.
You should be at least a bit computer savvy since some parts are not very well explained.

But READ ON please

To root basically you need,

• Android SDK manager, and to install google USB drivers (bootlock),
• Flashtool (not sony emma flashtool which you may download by mistake)
• FTF file with exploit available (this is a firmware which can be exploited to root)
• Unlock Bootloader
• A custom kernel if you actually want to do something with it such as recovery menu.
• Custom Rootkit tool.  

The link for FTF download is:
http://forum.xda-developers.com/showthread.php?t=2759934

And the link for the rootkit is:
http://forum.xda-developers.com/showthread.php?t=2783750

Flashtool can be obtained here:
http://www.mediafire.com/download/2ut97v5aszylr4w/flashtool-0.9.18.1-windows.exe
you need to install the flashtool drivers aswell as the z2 drivers

Custom Kernel for Z2:
http://forum.xda-developers.com/showthread.php?t=2735137

Unlock Bootloader:
http://developer.sonymobile.com/unlockbootloader/unlock-yourboot-loader/

ITS IMPORTANT FOR YOU TO READ THE THREAD, not all KERNEL VERSIONS are compatible with all firmwares:

• Xperia Z2 [D6502/03]
• • stock KitKat 4.4.2 FW
    • 17.1.2.A.0.314 - v10, v11
    • 17.1.1.A.0.402 - v06, v07, v08, v09
    • 17.1.A.2.69 - v01, v02, v03, v04, v05

Now in the video it does not talk about unlocking the bootloader, but this is required before you install custom firmware and Kernel,

the video is only for root and does not talk about anything else

THE BASIC STEPS FOR ROOT IS:

Again, this is what I did and what worked for me.

1. Unlock bootloader
2. Flash to xploitable FTF (firmware) using flashtool (select wipe all while flashing otherwise you may softbrick your device, i.e. bootloop)
3. Install Custom Kernel and recovery menu
4. Flash from recovery menu a pre rooted 5.1.1 lollipop
5. Flash from recovery menu Xposed Repository app (This enables you to get some apps that require root access)

IMPORTANT: Which FTF?

The video tutorial shows you how to downgrade to kitkat android and then exploit it to gain root access. I downloaded the firmware version

17.1.1.A.0.402

And the custom rootkit tool did not work for me, I had to search for a different toolkit online which ended up on this thread with download link for Easy Root Tool.

http://forum.xda-developers.com/showthread.php?t=2784900

Now, if you choose a wrong FTF you might encounter problems, such as the sony Z2 having no signal after rooting, (No service) and no IMEI, this must be because you have the wrong firmware for your CDA number.

The CDA number is unique to the region of the phone and to your carrier. It should be in the box they say, I didnt have my box.

I think the problem originates in if you download a locked firmware (Verizon USA, Vodafone IT, etc) on to a factory unlocked cellphone you are blocking it.

When I downgraded to 4.1.1 in order to gain root access, I had service, maybe its because I had luck who knows, but after this when I flashed a higher version pre rooted android firmware I had no IMEI
and sim card was not working.


Problems I encountered:
probably the most important part of the post

1. Did not select wipe all data on flashtool and I softbricked my device
2. After flashing to android kit kat (17.1.1.A.0.402) And rooting, I noticed it was too much hassle and tried to restore it to original firmware via Sony PC companion, and I couldnt since "The phone contains modified software can't update."  Apparently if you unlock the bootloader you loose automatic updates through the phone.
3. Flashing a custom 5.1.1 ftf, or maybe the Xposed repository made me loose simcard capability, no service, no signal
4. Device turned on automatically after connecting into flashmode in flashtools. Solved this by first selecting the firmware to flash and then after files are ready you connect in flashmode.
5. You might loose your DRM keys which are a certain specific key valid for your device in order to use exclusive sony Apps, suck as Track ID, apparently you have to back them up before flashing. I didnt knew, dont care either for such things but maybe you do!

How I went back to original no root access firmware:

I didnt have my CDA since I never got a box for this phone, since I knew my phone was bought in UAE and I had all my manuals in Arab I downloaded what I think was the firmware, I downloaded a firmware for an Unlocked D6503 for Saudi Arabia market. To download the original firmware I used XPERIFIRM

http://forum.xda-developers.com/crossdevice-dev/sony/pc-xperifirm-xperia-firmware-downloader-t2834142

And then once you download the firmaware you have to create the bundled .ftf file on flashtools excluding .TA files.

Hope this helps at least someone learn from My mistakes. Cheers.