[ Tutorial ] Nandroid Backup and CWM (ClockWorkMod) Recovery for S2 i9100

This tutorial is for starters who are looking to dig deep into their android devices.
Well Nandroid is a safe bet, as if something goes wrong one can restore the state at which they created a backup (just like restore point in windows).

So the problem arrives when we reboot our system into recovery (because every where it is written that we can create our backup (nandroid backup) in recovery mod). Stock recovery does not provide the options of backup and restore.

This problem was resolved by koushik dutta who created CWM (ClockWorkMod) Recovery, which gives us the option of BackingUp our data and Restoring it.

There are two ways to get the CWM Recovery mod.

• Flash a custom kernel with CWM Recovery. (No use if we want to backup everything in our stock ROM including stock kernel.)
• Using temporary CWM Recovery. (I prefer this one as this is safer and doesn't affect any system files and is removed after normal reboot).

I will be focusing more on second one but will explain first method as well.

Using temporary CWM Recovery:

Thanks to XDA user Phil3759 for creating temporary CWM Recovery:

To do the Nandroid Backup follow these steps:

1. Download cwm-touch-6.0.1.2-i9100.zip

2. Place the cwm-touch-6.0.1.2-i9100.zip file in the external SD card.

3. Now power off and boot into stock recovery (Vol Up + Home + Power) and choose "apply update from external storage".

4. Now locate and select your cwm-touch-6.0.1.2-i9100.zip. (this step gives a temporary flash that will disappear after reboot.)

5. Now you will be rebooted in the CWM Recovery.

6. In the Interface select "backup and restore"

7. Inside you will get many options like (backup, restore, delete, backup to internal SD card, restore from internal SD card.)

• If you select Backup, CWM will create Nandroid backup in External SD card (inside folder /CloclWorkMod/backup)
• If you select Backup to internal SD card, CWM will create Nandroid backup in Internal SD card (inside folder /CloclWorkMod/backup)

Or you can use recovery-clockwork-4.0.1.5-galaxys2.zip. This is the non touch version.

I have tried both and noticed the difference in the backup size.
With version 4.0.1.5 my stock JellyBean backup size was 2.23 GB whereas when I used 6.0.1.2 backup size was mere 19MB. I restored from both of them and restored version were working fine.

Other latest versions of CWM touch are also released and can be found here: [15.11.2012][ICS]PhilZ Touch 3.00 - CWM Based Recovery 6.0.1.5 (Temporary flash)

Flash a custom kernel with CWM Recovery:

Kernel Developers these days all support CWM Recovery. Few famous kernels for S2 i9100 are Siyah and Dorimanx (both supports dual boot and both use CWM Recoveries)

To flash Kernels you must have either Kernel.zip or Kernel.tar file (tar files are flashed using Odin or Mobile Odin while Zip files are flashed using Recovery (recovery flashing is same for all zip files))

Sources: [04.12.2012][ICS/JB]Universal Rooting for most phones, Any ROM, now with CWM6 and [15.11.2012][ICS]PhilZ Touch 3.00 - CWM Based Recovery 6.0.1.5 (Temporary flash)