CWM - ClockworkMod Recovery
What Is ClockworkMod Recovery And Explanation of its Functions
Every eager Android device owner will sooner or later encounter with CWM. If you don`t want to be stuck with the spoon-fed Samsung firmware forever, it will become your best friend. It is a brainchild of daddy Koushik Dutta – Koush (don`t know who mommy was but I`m sure she contributed in some way).
So what it does and how it looks? Read on.
A custom Android recovery basically replaces the stock recovery with one that lets you do all you can do with the stock recovery, plus a loads of more options to give you a lot more control on your device.
Recovery mode is a mode which is used for flashing ROM / Kernel / mods / bootanimations / themes etc. with CWM flashable zip. It also allows you to back up device data, preform several advanced recovery, restoration and maintenance operations on your Android device that aren’t possible with the stock recovery, and is one of the most common ways used to gain root access. However, for anyone new to Android customization and hacking, some of its options might prove to be challenging and/or confusing.
ENTER: you can do that with different rom mangers by selecting boot into recovery option (doh) or by pressing combo - volume up + home button + power key and hold `em until you see "Galaxy" logo. Welcome to the CWM. You`ll be greeted by this screen:
(don`t worry about the version numbers, the functions are pretty much the same for all of them)
You can navigate these options by using the Volume-Up and Volume-Down keys to highlight an option and the ‘Power’ key to enter/launch the highlighted option on most Android devices. If you have touch recovery installed you can choose desired option by simply pressing on it.
1. reboot system now: this one is self-explanatory
2. apply update from sdcard: this can be used for installation of any official or unofficial update, ROM, Kernel, theme etc. that is in a zip format installable from recovery, as long as the file is named update.zip and it has been placed on the root of your SD card (i.e. not in any sub-folder). Selecting this option (and most of the options featured below) will bring up a rather annoying confirmation prompt but this has saved us on multiple occasions from a lot of trouble we would have been into due to accidental key presses. This is what I`m talking about:
3. wipe data/factroy reset: this option wipes all user data on the device as well as cache. Doing this will leave your phone in the state it was in when you bought it or when any custom ROM was first installed. It will also wipe any sd-ext partition that you might have setup (more on this later)
4. wipe cache partition: wipes the cache partition of the device to clear all the data accumulated there over use. This is often used before installing a new ROM, app, Kernel or any similar mod via recovery
5. install zip from sdcard: this option brings up the following sub-menu:
• apply /sdcard/update.zip: this one is essentially the same as the ‘apply update from sdcard’ option of the main menu
• choose zip from sdcard: lets you install any zip file (with any name) from any location on your SD card. The file can be for a ROM, a Kernel, an application, a theme or any mod as long as it is in recovery-flashable zip format. This is the most widely used option for installing a ROM that you have downloaded and copied to your SD card. Entering this option will bring up a screen that will allow you to browse your SD card for the zip file and select it for installation as in this screenshot:
• toggle signature verification: turns the signature verification on and off. When signature verification is on, you will not be able to install any custom ROMs that haven’t been signed by the developers (most custom ROMs aren’t signed). Switching it off skips the signature verification check and proceeds with the installation
• toggle script asserts: seldom-used option for a vast majority of users. It simply turns script asserts on or off. If you don’t know about these (well, I don’t), it’s best not to change this option
• +++++Go Back+++++: no-brainer, takes you back to the main recovery menu
6. backup and restore: undisputedly one of the most important features provided by a custom recovery, the backup and restore feature – it goes by the name of Nandroid backup – allows you to take a snapshot of your phone’s entire internal memory including all partitions, and save it on the SD card, afterwards you can move it anywhere you want to (i.e. your computer). Here is how it looks:
• Backup: do you really need an explination? The number of them is not limited
• Restore: lets you restore a previously taken backup. Entering this option presents you with a list of existing backups from the SD card that you can choose from for restoration
• Advanced Restore: this option is similar to the Restore option but once a backup has been selected to be restored, this option allows you to choose what parts of it to restore. You can choose to restore the boot, system, data, cache and sd-ext partitions, as shown here:
7. mounts and storage: allows you to perform maintenance tasks on all the internal and external partitions of your android device:
• mount/unmount /system, /data, /cache, /sdcard or /sd-ext: these options let you toggle between mounting or unmounting these respective partitions. Most users don’t need to change these options
• format boot, system, data, cache, sdcard or sd-ext: these let you directly format any of these partitions. Take extreme care with this option as formatting any of these partitions will result in losing all data on them, especially the boot and system partitions. Formatting the system partition will remove your ROM and leave your phone without an operating system while wiping the boot partition may brick your phone unless you restore or flash another one before rebooting your device
• mount USB storage: lets you enable USB mass storage mode for your SD card right from recovery so that you can connect it to your computer via USB and transfer any files to/from it without having to leave recovery
8. advanced: this section contains a few options that can come handy quite often, especially wiping Dalvik cache, which is required before most ROM installations. If you want to install new stuff on your phone do exactly what the dev told you to do. Don`t go wiping caches just for the sake of it. Here are the options from this section:
• Reboot Recovery: lets you directly and very conveniently reboot from recovery right back into recovery. What is the use of it you ask? This is useful option for certain back-to-back installations that require the device to at least boot once between them
• Wipe Dalvik Cache: allows you to wipe the cache for the Dalvik virtual machine (the custom-built Java virtual machine for Android).This is required before most ROM installations and at other occasions too, for fixing some problems
• Wipe Battery Stats: wipes the saved battery usage statistics and effectively recalibrates the battery. Useful in various scenarios when Android isn’t showing correct battery levels
• Report Error: in case of errors, this feature can be used to save a log of recent ClockworkMod recovery operations on the SD card that you can later report from Android using ROM Manager
• Key Test: lets you press any of the hardware keys to see if they are properly functioning, and to see their key codes
• Partition SD Card: this option gives you a no-frills way to partition your SD card properly for use with ROMs that support data2ext (a very handy hack for low internal memory devices that enables an /sd-ext partition on the SD card to be used as the internal user data storage i.e. as the /data partition). Once this option is selected, you will be given options to choose the sizes for the /sd-ext partition as well as an optional /swap partition on the SD card, and will then automatically format it for you, leaving the remaining space for normal SD card usage. This option will wipe all data from your SD card so use it with caution!
• Fix Permissions: fixes the file permissions for the internal memory partitions back to default. This is very useful as a fix for several errors and Force-Closes that start appearing after you or an application you installed and provided root access end up messing up the permissions of important files