Well the Samsung Galaxy S2 has,
PDA-I9100XWKE8
Phone-I9100DDKE2
CSC-I9100DDKE2
Build Info – Wed May 18 13:55:45 KST 2011
Warning : You must understand that rooting requires flashing and if not done properly might brick your phone and render it useless. It might or might not break your warranty. You should take responsibilty of what your are doing to your phone. And if you don’t understand anything, do ask us in the comments section and make sure you understand each part of it completely before you flash your phone. Read the whole tutorial completely and make sure you understand everything before proceding.
Step by Step guide to Root Samsung galaxy S2 with CF Root & Latest & Original KE8 Kernel
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You’ll Need :
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- CF Root for SGS2 v3.6 with CWM3 ( XW_XEU_KE7 Kernel ) : Download
- KE8 Kernel : Download
- KE8 Kernel zImage File : Download
Step by Step guide to Root Indian SGS2
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- Extract the CF-Root-SGS2_XW_XEU_KE7-v3.6-CWM3.zip to get CF-Root-SGS2_XW_XEU_KE7-v3.6-CWM3.tar. ( Do not Extract this dot tar file to get the zImage )
- Extract Odin3-v1.85( both exe & ini file ).
- Run Odin3-v1.85 with administrative permissions by right clicking on it and running it as an Adminstrator.
- Select PDA checkbox and click on the PDA button.
- Now browse to & select CF-Root-SGS2_XW_XEU_KE7-v3.6-CWM3.tar that you just extracted in the first step.
- Now turn off the phone and start it in download mode by pressing & holding Volume Down Button + Home Button + Power Button simultaneously.
- Connect your SGS2 to computer using USB cable.
- You’ll see connected and COM Port info in the Left side of Odin3 ( top left & bottom ). If it doesn’t show, your phone is not recognized and perhaps the drivers are not installed.
- Just make sure Repartition is NOT checked.
- Click on the START Button & wait for the falshing to complete.
- If everything went fine you’ll see a sucess message in the message window on the bottom left and your phone will reboot.
- Your phone is now rooted. 
But wait, you still need to flash the original KE8 Kernel back. ( I already told you the benifits of KE8 kernel! ) And don’t worry, you won’t loose CWM after flashing the original kernel. Plus, this will also remove the Yellow exclamation triangle with a warning at the boot up. But it does NOT reset the custom kernel flash counter. You’ll need the KE8 Kernel zImage for this and this time you need to extract the zImage from dot zip file. Don’t get confused with the CF Rooted kernel and KE8 kernel.
Flash Stock KE8 Kernel to remove Warning triangle at the Boot Up :
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- Extract KE8 Kernel zImage to get the zImage file.
- Put the zImage file on the root folder of Internal SD Card. ( do not put it inside any folder of Internal SD Card. )
- Repeat the steps for flashing the kernel with Odin3 but with SamsungGalaxyS2-KE8kernel-zImage.tar file instead of CF-Root-SGS2_XW_XEU_KE7-v3.6-CWM3.tar.
- After rebooting your phone, go into CWM and select Flash Kernel, and select the zImage from KE8 kernel you previously put on your SD-card. The kernel will flash and the device will reboot.
- The Yellow Warning triangle will not be shown anymore, but you’ll have CWM. And in future if you select to flash your kernel with CWM Flash Kernel Option, it won’t increase the custom kernel flash counter.
- Enjoy your Rooted Samsung Galaxy S2 with latest KE8 kernel.