I rooted my S2 a few days back... there is a lot of info in the forums but spread all over the place and it took quite a long time to find the specific answers to some of the questions i had. Thus I've done a short form guide to help anyone looking to root and give them a bit of extended background and *hopefully* reduce all the copy threads/posts in the forum.
NB/ I'm no android expert. Please don't flame if something i've said is wrong. Let me know/PM me and I'll change it. This is only meant to be high level info!
1. What is rooting?
http://en.wikipedia.org/wiki/Rooting_(Android_OS)
2. What are the warranty implications?
Warranty is void BUT you can return the phone back to *stock* (standard manufacturer ship state) so, as long as you don't bone anything in the root process you can get still get warranty returns.
3. What is [recovery]/[kernel]/[rom]?
Your samsung device memory is separated into different partitions to load different parts of the software to make you device work.
http://www.villainrom.co.uk/vBwiki/index.php/Glossary_of_Android_Terms
Typically you have the kernel partition which tells the device what to load on power on), you have the system partition where your ROM (main operating system is loaded) and you have the recovery partition which allows a user to access and write to the system partition (i.e. load custom roms).
Only difference on the galaxy s2 is that the kernel partition and recovery partition linked. What this means for you is that if you change the kernel, you also change the recovery.
4. What is stock [kernel][firmware]?
http://xdaforums.com/showthread.php?t=1125282
Essentially the stock kernel is the original Samsung kernel shipped on the device (split into many different variants subject to location, sub model, carrier, date etc...) and firmware essentially is the kernel with the Samsung Rom.
5. My current kernel is KG*|KF*...n, can i install any other stock kernel? What are all the different stock kernels? Can I install one over mine?
http://xdaforums.com/showthread.php?t=1075278
Yes you can use any Kernel from any country as long as it is for SGS2 with the correct hardware
Check the models are the same.
6. What's the difference between Cf-Root and Clockworkmod and which do i want?
CF-Root is simply a customised version of the clockwordmod recovery. It still functions the same but cf-root has it's own app for making direct recovery calls from within android as CF-root doesn't function with Rom manager, where pure clockworkmod recovery does work with rom manager.
As far as I'm concerned, it's a question of whether you want to use Rom manager really?
7. How do I root the samsung galaxy S2?
All I will say is..ENSURE KIES IS NOT RUNNING IN SYSTEM TRAY OR TASK MANAGER. KILL THE WHOLE PROCESSS TREE IF YOU FIND IT BEFORE DOING ANY ROOTING!
CF-Root http://xdaforums.com/showthread.php?t=1103399
Clockworkmod http://xdaforums.com/showthread.php?t=1118693
N00b guide http://xdaforums.com/showthread.php?t=1126522
You can also use the root toolbox method for some stock firmwares without having to flash the recovery:
http://xdaforums.com/showthread.php?t=1319653
8. What is superoneclick and what is odin? Where do i get them?
Odin is a flash utility to allow you to push a kernel to your phone from your pc.
Superoneclick is a flash app that will root your phone from your pc.
If you don't want to use superoneclick then simply flash an unsecured kernel (i.e. CF-Root) using Odin and you'll get root already.
Look in the kernel posts and you'll find latest versions there.
9. Can i still get OTA (over the air) updates to my stock rom eventhough I've rooted?
you can update via Kies and root again. Kies wont detect if your phone is rooted or not as long as you are on Stock firmware.
10. How do i get back to stock (as if nothing has ever happened to the phone/factory ship)?
http://xdaforums.com/showthread.php?t=1075278
Flashing a full stock rom and kernel (firmware) using odin will remove everything.
11. What is this yellow exclamation mark and how do I get round it?
Whenever you access the download mode, and write a new kernel, your phone will know you've changed the kernel. The exclamation mark is simply a flag for samsung to easily know whether you've messed with the kernel on returns. You can easily get rid of it by using a jig OR re-flashing the stock kernel following an initial root...then re-flashing the zimage from the CWM image. - Jig is far easier and quicker though.
http://xdaforums.com/showpost.php?p=14283369&postcount=2
12. What is the custom binary download counter and how can I restore it?
A counter living in the kernel to record the number of times you've changed the kernel. Only way to remove it is to get a usb jig...
13. What is a jig and what does it do?
it's a little usb plugin from ebay then puts the phone into download mode (even if you bricked a kernel update) resets the kernel counter and removes the yellow exclamation mark.
Simply boot off the phone. Plug it in. The screen will say something like 'Erasing boot information'...then unplug it and re-boot. Very simple.
A jig is a cheap and essential piece of hardware that everyone rooting should invest in!
14. What is download mode and what is recovery mode and how do I access them?
Recovery > enter recovery with the key combination of Vol Up + Home + Power
Download > Accessible on all phones, regardless of kernel via Vol Down + Home +
http://xdaforums.com/showthread.php?t=1134290
15. What is deodexed|Odexed?
http://xdaforums.com/showpost.php?p=16461907&postcount=2
http://www.villainrom.co.uk/vBwiki/index.php/Glossary_of_Android_Terms
16. Once rooted I can install custom roms, but can I overwrite the kernel?
Yes, so long as the kernel is compatible with the hardware and in some cases the rom.
17. I've rooted and put CF-Root XWKF(...n)...But I want to put a different kernel on and still have the CWM recovery?
Simply flash the CF-Root over the current CF-Root. However if you are updating a major version (i.e. CWM 4 to CWM 5) just check on CF-Root's thread first.
18. I've pwned my device? What do I do now?
Get a jig to put back into download mode and then flash the original stock firmware.
19. My device is sim locked and/or full of carrier apps? How can I get rid?
To get rid of carrier branding and apps simply flash a different firmware/rom that isn't branded from a carrier. See questions 4 and 5 above for lists of the different stock firmwares.
To get rid of the sim lock you have two options:
1. Root and then use one of the apps from market place (mixed success across the boards); or,
2. Extract some data from your phone in hex code and try and calculate the unlock code yourself.
I bought mine sim free so not done any of this but a quick scan of the forums turned up these two posts which may be useful.
http://xdaforums.com/showthread.php?t=1207513&referrerid=2648941
http://xdaforums.com/showthread.php?t=1064978&referrerid=2648941
20. What is a 'cooked' rom?
Cooked roms are just roms that someone has made based on the stock rom with slight high level changes. They are different from developed roms such as Cyanogen or Villainrom which receive significant low level modifications and developments.
Check out the Rom kitchen project which when released in stable version will allow you to build your own rom on the fly and select all the apps etc.. you want in it: brilliant example of the benefits of Android!
http://www.romkitchen.org/beta/index.php
21. What is CSC and how do i change my ROM CSC?
CSC = consumer software customisation. The file contains the software packages specific to that region, carrier branding and also APN settings for data connection, SMS, MMS etc...
Three ways to change it (NB it will wipe your device!):
1. Flash a multiCSC ROM and that use CSC Select from Market;
2. Flash a multiCSC ROM and type *#272*Device IMEI# into the dial pad and selecting the csc of your choice;
3. Flash a ROM using ODIN, then flash the desired CSC separately using ODIN.
22. Do you just install Rom over an existing?
Some people do and 9 times out of 10 it works, however I personally boot into recovery, wipe all data/factory reset and wipe Davlik cache > then power off > boot into download mode and install the new rom as above. Best way to ensure a 100% clean install.
23. What is the best way to go from Android 2.x to Android 4.x (Ice Cream Sandwich)?
I struggled trying to get Titanium to quickly and efficiently migrate my data (I'm sure it's very possible but I didn't have the time nor inclination to work around it) therefore I just restored my apps data after manually installing the apps from the marketplace. Once you have a stable working phone on ICS future titanium backup/restores are easy as normal.
24. Titanium Backup? What's the difference in app colour?
Menu => Legend;
Green = App - with data that you should backup;
White = App - should be fine to backup;
Red = System app/service - Wouldn't backup as typically installed by default.
Other tools apps that will be helpful are Titanium Backup (from Android Marketplace https://market.android.com/details?id=com.keramidas.TitaniumBackup&hl=en) and also get a Dropbox account (for free) from Free 2GB Cloud Storage from Dropbox as Titanium can sync to Dropbox.
25. Anything else of note?
Other tools apps that will be helpful are Titanium Backup (from Android Marketplace https://market.android.com/details?id=com.keramidas.TitaniumBackup&hl=en) and also get a Dropbox account (for free) from Free 2GB Cloud Storage from Dropbox as Titanium can sync to Dropbox.
Also slightly linked, if every you want a good UK based hosting for blogs/web/dev - I couldn't recommend TsoHost enough. They are the best hosting company I've ever worked with! Unlimited sql databases and PHP setting modification! If you want 10% off all hosting packages use the code 'wibbsy' at checkout!
NB/ I'm no android expert. Please don't flame if something i've said is wrong. Let me know/PM me and I'll change it. This is only meant to be high level info!
1. What is rooting?
http://en.wikipedia.org/wiki/Rooting_(Android_OS)
2. What are the warranty implications?
Warranty is void BUT you can return the phone back to *stock* (standard manufacturer ship state) so, as long as you don't bone anything in the root process you can get still get warranty returns.
3. What is [recovery]/[kernel]/[rom]?
Your samsung device memory is separated into different partitions to load different parts of the software to make you device work.
http://www.villainrom.co.uk/vBwiki/index.php/Glossary_of_Android_Terms
Typically you have the kernel partition which tells the device what to load on power on), you have the system partition where your ROM (main operating system is loaded) and you have the recovery partition which allows a user to access and write to the system partition (i.e. load custom roms).
Only difference on the galaxy s2 is that the kernel partition and recovery partition linked. What this means for you is that if you change the kernel, you also change the recovery.
4. What is stock [kernel][firmware]?
http://xdaforums.com/showthread.php?t=1125282
Essentially the stock kernel is the original Samsung kernel shipped on the device (split into many different variants subject to location, sub model, carrier, date etc...) and firmware essentially is the kernel with the Samsung Rom.
5. My current kernel is KG*|KF*...n, can i install any other stock kernel? What are all the different stock kernels? Can I install one over mine?
http://xdaforums.com/showthread.php?t=1075278
Yes you can use any Kernel from any country as long as it is for SGS2 with the correct hardware
Check the models are the same.
6. What's the difference between Cf-Root and Clockworkmod and which do i want?
CF-Root is simply a customised version of the clockwordmod recovery. It still functions the same but cf-root has it's own app for making direct recovery calls from within android as CF-root doesn't function with Rom manager, where pure clockworkmod recovery does work with rom manager.
As far as I'm concerned, it's a question of whether you want to use Rom manager really?
7. How do I root the samsung galaxy S2?
All I will say is..ENSURE KIES IS NOT RUNNING IN SYSTEM TRAY OR TASK MANAGER. KILL THE WHOLE PROCESSS TREE IF YOU FIND IT BEFORE DOING ANY ROOTING!
CF-Root http://xdaforums.com/showthread.php?t=1103399
Clockworkmod http://xdaforums.com/showthread.php?t=1118693
N00b guide http://xdaforums.com/showthread.php?t=1126522
You can also use the root toolbox method for some stock firmwares without having to flash the recovery:
http://xdaforums.com/showthread.php?t=1319653
8. What is superoneclick and what is odin? Where do i get them?
Odin is a flash utility to allow you to push a kernel to your phone from your pc.
Superoneclick is a flash app that will root your phone from your pc.
If you don't want to use superoneclick then simply flash an unsecured kernel (i.e. CF-Root) using Odin and you'll get root already.
Look in the kernel posts and you'll find latest versions there.
9. Can i still get OTA (over the air) updates to my stock rom eventhough I've rooted?
you can update via Kies and root again. Kies wont detect if your phone is rooted or not as long as you are on Stock firmware.
10. How do i get back to stock (as if nothing has ever happened to the phone/factory ship)?
http://xdaforums.com/showthread.php?t=1075278
Flashing a full stock rom and kernel (firmware) using odin will remove everything.
11. What is this yellow exclamation mark and how do I get round it?
Whenever you access the download mode, and write a new kernel, your phone will know you've changed the kernel. The exclamation mark is simply a flag for samsung to easily know whether you've messed with the kernel on returns. You can easily get rid of it by using a jig OR re-flashing the stock kernel following an initial root...then re-flashing the zimage from the CWM image. - Jig is far easier and quicker though.
http://xdaforums.com/showpost.php?p=14283369&postcount=2
12. What is the custom binary download counter and how can I restore it?
A counter living in the kernel to record the number of times you've changed the kernel. Only way to remove it is to get a usb jig...
13. What is a jig and what does it do?
it's a little usb plugin from ebay then puts the phone into download mode (even if you bricked a kernel update) resets the kernel counter and removes the yellow exclamation mark.
Simply boot off the phone. Plug it in. The screen will say something like 'Erasing boot information'...then unplug it and re-boot. Very simple.
A jig is a cheap and essential piece of hardware that everyone rooting should invest in!
14. What is download mode and what is recovery mode and how do I access them?
Recovery > enter recovery with the key combination of Vol Up + Home + Power
Download > Accessible on all phones, regardless of kernel via Vol Down + Home +
http://xdaforums.com/showthread.php?t=1134290
15. What is deodexed|Odexed?
http://xdaforums.com/showpost.php?p=16461907&postcount=2
http://www.villainrom.co.uk/vBwiki/index.php/Glossary_of_Android_Terms
16. Once rooted I can install custom roms, but can I overwrite the kernel?
Yes, so long as the kernel is compatible with the hardware and in some cases the rom.
17. I've rooted and put CF-Root XWKF(...n)...But I want to put a different kernel on and still have the CWM recovery?
Simply flash the CF-Root over the current CF-Root. However if you are updating a major version (i.e. CWM 4 to CWM 5) just check on CF-Root's thread first.
18. I've pwned my device? What do I do now?
Get a jig to put back into download mode and then flash the original stock firmware.
19. My device is sim locked and/or full of carrier apps? How can I get rid?
To get rid of carrier branding and apps simply flash a different firmware/rom that isn't branded from a carrier. See questions 4 and 5 above for lists of the different stock firmwares.
To get rid of the sim lock you have two options:
1. Root and then use one of the apps from market place (mixed success across the boards); or,
2. Extract some data from your phone in hex code and try and calculate the unlock code yourself.
I bought mine sim free so not done any of this but a quick scan of the forums turned up these two posts which may be useful.
http://xdaforums.com/showthread.php?t=1207513&referrerid=2648941
http://xdaforums.com/showthread.php?t=1064978&referrerid=2648941
20. What is a 'cooked' rom?
Cooked roms are just roms that someone has made based on the stock rom with slight high level changes. They are different from developed roms such as Cyanogen or Villainrom which receive significant low level modifications and developments.
Check out the Rom kitchen project which when released in stable version will allow you to build your own rom on the fly and select all the apps etc.. you want in it: brilliant example of the benefits of Android!
http://www.romkitchen.org/beta/index.php
21. What is CSC and how do i change my ROM CSC?
CSC = consumer software customisation. The file contains the software packages specific to that region, carrier branding and also APN settings for data connection, SMS, MMS etc...
Three ways to change it (NB it will wipe your device!):
1. Flash a multiCSC ROM and that use CSC Select from Market;
2. Flash a multiCSC ROM and type *#272*Device IMEI# into the dial pad and selecting the csc of your choice;
3. Flash a ROM using ODIN, then flash the desired CSC separately using ODIN.
22. Do you just install Rom over an existing?
Some people do and 9 times out of 10 it works, however I personally boot into recovery, wipe all data/factory reset and wipe Davlik cache > then power off > boot into download mode and install the new rom as above. Best way to ensure a 100% clean install.
23. What is the best way to go from Android 2.x to Android 4.x (Ice Cream Sandwich)?
I struggled trying to get Titanium to quickly and efficiently migrate my data (I'm sure it's very possible but I didn't have the time nor inclination to work around it) therefore I just restored my apps data after manually installing the apps from the marketplace. Once you have a stable working phone on ICS future titanium backup/restores are easy as normal.
24. Titanium Backup? What's the difference in app colour?
Menu => Legend;
Green = App - with data that you should backup;
White = App - should be fine to backup;
Red = System app/service - Wouldn't backup as typically installed by default.
Other tools apps that will be helpful are Titanium Backup (from Android Marketplace https://market.android.com/details?id=com.keramidas.TitaniumBackup&hl=en) and also get a Dropbox account (for free) from Free 2GB Cloud Storage from Dropbox as Titanium can sync to Dropbox.
25. Anything else of note?
Other tools apps that will be helpful are Titanium Backup (from Android Marketplace https://market.android.com/details?id=com.keramidas.TitaniumBackup&hl=en) and also get a Dropbox account (for free) from Free 2GB Cloud Storage from Dropbox as Titanium can sync to Dropbox.
Also slightly linked, if every you want a good UK based hosting for blogs/web/dev - I couldn't recommend TsoHost enough. They are the best hosting company I've ever worked with! Unlimited sql databases and PHP setting modification! If you want 10% off all hosting packages use the code 'wibbsy' at checkout!
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