Hi mates,
When we are flashing a Custom Rom from the CWM, we are normally instructed by the Devs only to do few steps on CWM like “Wipe Data/Factory Data Reset, Wipe Cache etc.. which we simply follow, but most of the people don’t know, including me, what these options and many other options of CWM are really standing for.
When I googled, I could not find a thread which explains about these options in a single thread, so I would like to share with my friends about what I found the Common Options of the CWM here...
Obviously these are commonly applicable for all the devices which are having CWM, but I am always concern about my favorite Galaxy S II.
People who are completely new to Recovery and these options, I suggest them to read this thread first and give a thanks to it's author.
What Is Recovery & Download Mode?
The oder and segregation of the below items in the CWM menu may vary or some of them may be removed in different custom recoveries designed by respective Developer.
CLOCKWORKMODE BASED RECOVERY MENU
1) Reboot Menu :
reboot system now
This one is self-explanatory.
2) Install Menu :
choose zip from (internal/ external) 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.
apply /sdcard/update.zip
This one is essentially the same as the ‘apply update from sdcard’ option of the main menu. 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.
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 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.
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 (I don’t), it’s best not to change this option.
3) Wipe Menu
wipe data/factory 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. (see more about sd-ext below under partition)
wipe cache partition
This is a good practice to do this before flashing any ROM. The /cache partition just stores temporary files that are not critical to device operation and can be re-generated easily, this 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.
Wipe Dalvik Cache
Allows you to wipe the cache for the Dalvik virtual machine. The dalvik cache wipe is quite similar to cache wipe but it stores the post ran java applications. Since Android is JAVA based, it uses the same java virtual machine for compiling. The dalvik cache just stores post-compiled applications in order to speed up the system. Wiping this just forces the system to re-cache those application. It causes no problems but a slight hint of lag on first boot. 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.
4) Nandroid menu
backup and restore Undoubtedly one of the most important features provided by a custom recovery, the backup and restore feature – also known as 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.
Backup
Takes a Nandroid backup, as explained above.
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 (new options are available separately to restore from external or internal SDcard in the latest CWM)
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.
5) Storage menu
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, /emmc.
These options let you toggle between mounting or unmounting these respective partitions. Most users don’t need to change these options.
format 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. See below more explanation about these partitions.
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.
6) Advanced
This section contains a few options most users will not require, Here are the options from this section:
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.
PARTITIONS :
The Android uses several partitions to organize files and folders on the device. Each of these partitions has a distinct role in the functionality of the device, but not many Android users know the significance of each partition and its contents. In this guide, we will take you on a tour of Android partitions, what they contain and what can be the possible consequences of modifying their content.
Let’s start with a list of standard internal memory partitions on Android phones and tablets. These are:
• /boot
• /system
• /recovery
• /data
• /cache
• /misc
In addition, there are the SD card partitions.
• /sdcard
• /sd-ext
Note that only /sdcard is found in all Android devices and the rest are present only in select devices. Let’s now take a look at the purpose and contents of each of these partitions.
/boot
This is the partition that enables the phone to boot, as the name suggests. It includes the bootloader and the kernel. Without this partition, the device will simply not be able to boot. Wiping this partition from recovery should only be done if absolutely required and once done, the device must NOT be rebooted before installing a new one, which can be done by installing a ROM that includes a /boot partition.
/system
This partition basically contains the entire operating system, other than the kernel and the bootloader. This includes the Android user interface as well as all the system applications that come pre-installed on the device. Wiping this partition will remove Android from the device without rendering it unbootable, and you will still be able to put the phone into recovery or bootloader mode to install a new ROM.
/recovery
The recovery partition can be considered as an alternative boot partition that lets you boot the device into a recovery console for performing advanced recovery and maintenance operations on it. We have already learnt about this partition and its contents above.
/data
Also called userdata, the data partition contains the user’s data – this is where your contacts, messages, settings and apps that you have installed go. Wiping this partition essentially performs a factory reset on your device, restoring it to the way it was when you first booted it, or the way it was after the last official or custom ROM installation. When you perform a wipe data/factory reset from recovery, it is this partition that you are wiping.
/cache
This is the partition where Android stores frequently accessed data and app components. Wiping the cache doesn’t effect your personal data but simply gets rid of the existing data there, which gets automatically rebuilt as you continue using the device.
/misc
This partition contains miscellaneous system settings in form of on/off switches. These settings may include CID (Carrier or Region ID), USB configuration and certain hardware settings etc. This is an important partition and if it is corrupt or missing, several of the device’s features will will not function normally.
/sdcard
This is not a partition on the internal memory of the device but rather the SD card. In terms of usage, this is your storage space to use as you see fit, to store your media, documents, ROMs etc. on it. Wiping it is perfectly safe as long as you backup all the data you require from it, to your computer first. Though several user-installed apps save their data and settings on the SD card and wiping this partition will make you lose all that data.
On devices with both an internal and an external SD card – devices like the Samsung Galaxy SII – the /sdcard partition is always used to refer to the internal SD card. For the external SD card – if present – an alternative partition is used, which differs from device to device. In case of Samsung Galaxy S series devices, it is /sdcard/External_sd while in many other devices, it is /sdcard2. Unlike /sdcard, no system or app data whatsoever is stored automatically on this external SD card and everything present on it has been added there by the user. You can safely wipe it after backing up any data from it that you need to save.
/sd-ext
This is not a standard Android partition, but has become popular in the custom ROM scene. It is basically an additional partition on your SD card that acts as the /data partition when used with certain ROMs that have special features called APP2SD+ or data2ext enabled. It is especially useful on devices with little internal memory allotted to the /data partition. Thus, users who want to install more programs than the internal memory allows can make this partition and use it with a custom ROM that supports this feature, to get additional storage for installing their apps. Wiping this partition is essentially the same as wiping the /data partition – you lose your contacts, SMS, market apps and settings.
Now whenever we install a ROM or mod that requires we to wipe certain partitions before the installation, we should be in a better position to know what we are losing and what not and thus, we’ll know what to backup and what not.
Best Regards
http://forum.xda-developers.com/showthread.php?t=1134290
Yep. Been done before a long time ago. Tho I do admire your initiative in putting the info together
Stifler69 said:
http://forum.xda-developers.com/showthread.php?t=1134290
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No Doubt this one should be on the top of this thread,
What a simple and awesome explanation about the Recovery & Download mode, many thanks to pulser_g2
I know, majority of users only need the simple steps and shortcuts, they don’t care what’s happening internally and theoretically, but some are really curious to know…
Many thanks mate....
zaheedahmed said:
No Doubt this one should be on the top of this thread,
What a simple and awesome explanation about the Recovery & Download mode, many thanks to pulser_g2
I know, majority of users only need the simple steps and shortcuts, they don’t care what’s happening internally and theoretically, but some are really curious to know…
Many thanks mate....
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Click to collapse
Nah mate you do what you have to do. It is a good thread and provides good information. Nice work. Just wanted to show you Pulsers thread as well though because he has done something similar to yours long time ago..But anyway good work and if you need any help let me know
Thanks, will save later text in PDF and keep it on PC just to have one more tutorial about things
Awesome write up!! Brilliant!
As you are so knowledgeable about CWM, perhaps I can ask you a question?
When I do a backup, it says that no external SD card was found, so it skipped the external?
When I check under mounts, the only option for the external SD card is to UNmount.... This would suggest that the card is mounted, correct?
So how would I go about backing up the external card too?
Thanks!
Sent from my SGH-I727R using xda premium
Question, if i do nandroid backhp through CWM, i suppose it saves files that i dl such as apps/games, or i need to download later again 600mb+?
Sent by powaaaaah of GT-I9100 Taparatatatalk!
shaggyskunk said:
Awesome write up!! Brilliant!
As you are so knowledgeable about CWM, perhaps I can ask you a question?
When I do a backup, it says that no external SD card was found, so it skipped the external?
When I check under mounts, the only option for the external SD card is to UNmount.... This would suggest that the card is mounted, correct?
So how would I go about backing up the external card too?
Thanks!
Sent from my SGH-I727R using xda premium
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Click to collapse
Thank you for your appreciation,
I would like to express once again as I mentioned in the starting of the thread that this is only a humble effort of the undersigne that I searched for such information and combined at one place here....
As far as I know about your problem of SD card storage, this is a compatibility issiue which varries on one custom recovery to another, also one SD card to another. such issues are fixed by developers in their latest versions of recoveries.
I experienced once the same issue which was resolved when I changed my SD card.
And my current (touch) recovery of Redpill v1.3 allows me to Backup and restore from external SD card with all available options flowlessly.
Thanks
X-Plosiv said:
Question, if i do nandroid backhp through CWM, i suppose it saves files that i dl such as apps/games, or i need to download later again 600mb+?
Sent by powaaaaah of GT-I9100 Taparatatatalk!
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Click to collapse
Between CWM & Titanium, you should not have to download anything.
Sent From my Two Tin Cans & String Device on The Wookie Network
X-Plosiv said:
Question, if i do nandroid backhp through CWM, i suppose it saves files that i dl such as apps/games, or i need to download later again 600mb+?
Sent by powaaaaah of GT-I9100 Taparatatatalk!
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Click to collapse
Of course it backs up all your installed apps and system data along with the ROM, but it do not back up the additional data which is downloaded and stored in User's partition of your SD card by the applications, such data will remain on your SD card untill you format it, available to support your apps when you return to the previous ROM.
awsome eplanation
as above posts say awsome explinationculdnt b clearer now then all
zaheedahmed said:
Of course it backs up all your installed apps and system data along with the ROM, but it do not back up the additional data which is downloaded and stored in User's partition of your SD card by the applications, such data will remain on your SD card untill you format it, available to support your apps when you return to the previous ROM.
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Yes, but when I do format/wipe all, I guess then it deletes all that is on SD card as well, such as game files and music? If so, I'd rather just copy paste it on my PC, then after doing all wipes and formats, just copy back from PC
Zaheed, you are far too humble! Your post was brilliant, informative & timely.
Sent From my Two Tin Cans & String Device on The Wookie Network
X-Plosiv said:
Yes, but when I do format/wipe all, I guess then it deletes all that is on SD card as well, such as game files and music? If so, I'd rather just copy paste it on my PC, then after doing all wipes and formats, just copy back from PC
Click to expand...
Click to collapse
When you do normal wipes (data/ factory reset, cache, dalvik) before installing/restoring ROM, it won't touch any data which is saved in your SD Card normally, but it is more safer if you back such application data to you PC which normally find in a folder "Android/ Data /xxx" in the root of SDcard
Thanks for info.
I have read a lot on this but am still nor clear whether a wipe data/factory reset includes a full cache wipe. Most rom install instructions tell you to do both, but it seems a wipe cache is redundant if you factory reset.
SimboXXX said:
Thanks for info.
I have read a lot on this but am still nor clear whether a wipe data/factory reset includes a full cache wipe. Most rom install instructions tell you to do both, but it seems a wipe cache is redundant if you factory reset.
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Yes, you are right, I also understand the same, but the option for merely wiping cache is kept for using in some odd situations, like when we fingered to the ROM and got some error, then we got a no-wipe version of the existing ROM to reflash, such case we need only to wipe cache…. I have got an error recently on CWM when I reflashed my no-wipe Checkrom v6 without wiping anything, then I wiped only cache, problem solved…..
what ever may be the theory, do as the developers directed for their ROM…..NO RISK
shaggyskunk said:
Zaheed, you are far too humble! Your post was brilliant, informative & timely.
Sent From my Two Tin Cans & String Device on The Wookie Network
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thanks mate...
Thanks for the thread, you can never know too much. On second thoughts, there's probably no danger of that.
What would be really good if you have the knowledge, is a detailed guide on CWM Edify scripting. I'm sure many people would find that useful, especially me. There doesn't seem to be a lot of good guides or information on the language, at least I can't find them yet. If you have any good links I'd definitely appreciate it as well.
Here's another bit of information, that answered a question I had....
In case anyone else has this question...
Here is the answer from:
http://android.stackexchange.com/qu...ter-no-sd-ext-found-skipping-backup-of-sd-ext
" This means you do not have an ext3/4 partition on your sdcard. This really ins't a big deal, this is like a legacy part of the nandroid backup process. CM doesn't "officially" support the sd-ext partition any more anyhow."
Hope it helps someone else... In the end, the answer is pretty straight forward.
Sent From my Two Tin Cans & String Device on The Wookie Network
Sent from Down The Rabbit Hole, using Tapatalk 2
Related
To all the devs around here. Great work by the way!! Not that I wanna know all the technical details, but it would be nice to get an overview of how things work together on the GT.
I have a PC Windows and Linux background, but I don't fully understand as of yet how things blend together on the tab.
Can you explain a few things;
How come flashing a ROM doesn't wipe the entire system? Is a rom pretty much the same as a ghost image for PC?
How are system files (OS) differentiate with your media/videos for example.
If you install a custom kernel (see pershoot for example), will installing a rom overwrite the newly installed kernel, or do they reside in a different place on the disk? If so, can you explain.
How are things separated on the GTAB? Where is CWM installed, is it something similar to a PC bios that you flash with a custom bios?
The internal memory is split up (probably partitioned but it could be something else) into the system area and the user area that acts like the sd card does in most android devices. System files are in the system area, your media files are on the part acting like an sd card.
ROMs contain their own kernel which will overwrite your custom kernel but as long as the custom kernel is compatible with the ROM you can flash the custom kernel over the ROMs kernel. Im not sure if touchwiz and non-touchwiz need different kernels like htc sense.
I dont know where cwm is installed but its separate from the os.
That's a good start, but id love to hear more about the inner workings of everything. I don't want to know if X is compatible with Y. I just want to know how to work together and why A isnt overwriting B.
Wrong section buddy, go to the Q&A
i going to oversimplify this a bit to focus on the relevant portions of ROM flashing.
System partition - this is where the android operating system is installed. It contains the all of the files and apks for android to run. System apks are located here - stuff like the browser, gmail, contacts, calendar, etc. Just the apps are stored here, not their settings.
Boot partition - this is the kernel
Data partition - this is where all of your data is stored. Data includes all settings (including os settings like wifi passwords, brightness level, etc.), as well as any apps you have downloaded as well as their settings and data (example, the angry birds apk is here as well the angry birds data that contains your game progress.) Also the setting and data for the system apks mentioned above (like Gmail and the browser) are stored here.
Sdcard - on android phones this is a separate partition, but on tablets it is a pseudo partition - really just a folder on the data partition but treated like a separate partition most of the time.
When you flash a ROM without wiping anything you are just overwriting the system and boot partitions, that's why all of your data stays in tact.
Cool thanks, can someone describe how does the different options in CWM affect those partitions?
What is wiped when you do a factory reset? cache? and davlik?
I would also be interested in knbowing where does CWM resides.
Thanks
mickey78 said:
Cool thanks, can someone describe how does the different options in CWM affect those partitions?
What is wiped when you do a factory reset? cache? and davlik?
I would also be interested in knbowing where does CWM resides.
Thanks
Click to expand...
Click to collapse
A factory reset in cwm wipes data and cache. Davlik cache is wiped separately through the advanced menu. You can also wipe system, data, cache, and sdcard in the mounts section of cwm.
Cwm is a replacement of the stock recovery partition that shipped on your tablet or phone.
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Moving to General
Hi!
So I'm running civato's FLEXREAPER-R6 ICS 4.0.3 ROM on my Iconia A500 after using timmyDean's "root-3.2.1-V4.7z" method to root my stock HC 3.2.1 ROM. I had ClockworkMod Recovery v5.0.2.3 (rev 1.3.4 by thor2002ro) and was unable to do a full Nandroid backup so I upgraded to the latest ClockworkMod Recovery v5.5.0.x (rev 1.7 by thor2002ro) but I'm still having the same issue.
When I try to backup data I get the error "Error making a backup image of /data!" and then when I look at the sdcard in \clockworkmod\backup\YYYY-MM-DD.HH.MM.SS I see "data.ext4.tar" and the size is 4,294,967,296 bytes), which is exactly the 4GB filesize limit on a FAT32 partition. Looking inside the data.ext4.tar file, I see data/app and all the .APK installer files for apps installed on my Iconia plus a few .ZIP files as well. ES File Explorer won't show me how big /data/app is but DiskUsage says it's 4.7GB. From what I'm reading Android needs a copy of all the APK user-installed app installation files of in /data/app so that it can restore the default data/configuration when requested (under Settings/Apps/Manage Apps/Delete Data & Cache). So...how can I get a successful Nandroid backup if I have more than 4GB of apps installed? Can the data portion be broken up into <4GB chunks? Or can Nandroid/Recovery be updated to support exFAT or NTFS? Or would it be safe to exclude /data/app from the backups?
Since I've been unable to do the Recovery/Nandroid backup of "data", I've been doing a custom backup of everything except for data and then backing up all my installed apps and settings from inside the OS with Titanium Backup. But with this method, a catastrophic failure would still require me to use Recovery to restore the OS and then use Titanium to restore app my apps.
What's the solution?
You can try doing several backups, in other words, do a nandroid backup of /data separate from the other back ups of /system /boot /recovery and other paritions. Then when you have to restore, first restore the backup with your system partitions and then restore your data partition afterwards. You are probably backing up to many things to have a nandroid file that large anyway. When you do a full data wipe it does not wipe the data on the internal sd card only the data on the data partition.
cruise350 said:
You can try doing several backups, in other words, do a nandroid backup of /data separate from the other back ups of /system /boot /recovery and other paritions. Then when you have to restore, first restore the backup with your system partitions and then restore your data partition afterwards. You are probably backing up to many things to have a nandroid file that large anyway. When you do a full data wipe it does not wipe the data on the internal sd card only the data on the data partition.
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Hey cruise350! I have an Evo 3D as well. I'm running Virus's "Eternity 3.0 r193 ROM" with the Stock theme on my Evo 3D, how about you? Anyway, I have tried doing separate Nandroid backups. I can backup everything but "data" and that will complete just fine. I don't see any way to break up the "data" backup into multiple smaller backups. But as I said, if I backup everything else with Nandroid, I feel pretty confident that I can restore all my apps/data with Titanium.
Would it be safe to try to move /data/app temporarily somewhere else (such as /mnt/sdcard), do the Nandroid data backup, and then move it back?
It seems to me that doing full wipe (system, data, cache, dalvik cache, superwipe, etc) would wipe out /data and everything underneath (including /data/apps) but that it would get recreated automatically when I restore everything with TB, right?
The way to get rid of that problem once and for all is to format your SD card as EXT4... You won't be able to read it with non-Linux (or BSD) OSes after that, though. Mounting via USB should still work, as this doesn't access the SD filesystem directly...
I would try changing recoveries then, I am using RA recovery and it has a compress backup feature. It takes about 45 minutes to do a nandroid when compressing but it cuts the size of the backup significantly. I bet RA will solve your problem though. And, I am running Steelrom on my Evo 3d. It's really stable, has some good tweaks, and the battery life is incredible.
haag498 said:
The way to get rid of that problem once and for all is to format your SD card as EXT4... You won't be able to read it with non-Linux (or BSD) OSes after that, though. Mounting via USB should still work, as this doesn't access the SD filesystem directly...
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Click to collapse
Thanks, haag498. That's an interesting idea. So any Android OS or Recovery would be able to read/write to an EXT4-fomatted SD card? It would work in both my Iconia A500 and my Evo 3D both in Recovery and inside the OS? That might be a good option. I see that EXT4 supports very large filesizes so that problem would go away. What tool would you recommend for formatting the SD card with that filesystem? Can it be done from inside Android?
Not being able to mount the filesystem natively in Windows might present occasional inconveniences but it shouldn't be a major problem as long as the Android devices can present the storage as USB Mass Storage mode. That being said, I have some issues with the Iconia when accessing the storage over USB. Namely, when I try to move files and folder off the device or delete them from Windows when attached via USB, the task often won't complete. I've worked around the problem by just doing internal moves, deletes and renames from inside Android (using ASTRO or ES File Explorer) and, if necessary, mounting the SD card directly in my Windows PC, which won't be possible anymore.
cruise350 said:
I would try changing recoveries then, I am using RA recovery and it has a compress backup feature. It takes about 45 minutes to do a nandroid when compressing but it cuts the size of the backup significantly. I bet RA will solve your problem though. And, I am running Steelrom on my Evo 3d. It's really stable, has some good tweaks, and the battery life is incredible.
Click to expand...
Click to collapse
Okay...so if I wanted to install RA Recovery instead, would I flash that from inside CMR? I have "Acer Recovery Installer" installed as well but I believe the version of CMR I'm using is newer than what that tool would have been able to install. So, what's the procedure to switch to RA from CMR? Any other features of RA that you prefer?
JesseAaronSafir said:
Okay...so if I wanted to install RA Recovery instead, would I flash that from inside CMR? I have "Acer Recovery Installer" installed as well but I believe the version of CMR I'm using is newer than what that tool would have been able to install. So, what's the procedure to switch to RA from CMR? Any other features of RA that you prefer?
Click to expand...
Click to collapse
You can flash from within CWM. If you look in the RA threads, you will find some flashable versions. I use 3.15, as I have been lazy to update to 3.16.
No wipes needed. Just install zip from SD
http://forum.xda-developers.com/showpost.php?p=22392691&postcount=104
JesseAaronSafir said:
Thanks, haag498. That's an interesting idea. So any Android OS or Recovery would be able to read/write to an EXT4-fomatted SD card?
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Click to collapse
They should, if they're using a reasonably up-to-date Linux kernel, as EXT4 is built in for these... If you want to be absolutely sure, use EXT2/3 (they're pretty much identical from a user point of view), which still support large files and all, but are somewhat slower (and they can't use more than 4TB, which shouldn't be an issue anyway...).
JesseAaronSafir said:
It would work in both my Iconia A500 and my Evo 3D both in Recovery and inside the OS?
Click to expand...
Click to collapse
Read above.
JesseAaronSafir said:
That might be a good option. I see that EXT4 supports very large filesizes so that problem would go away. What tool would you recommend for formatting the SD card with that filesystem? Can it be done from inside Android?
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Click to collapse
Formatting the SD card can be done from any Linux live CD (Ubuntu, Knoppix, ...) or from within Android (if you're rooted and have a chroot Linux) using parted (or cfdisk) or some GUI tool like gparted... Internally, they'll all use mkfs.ext4, which is anything but user-friendly, though...
JesseAaronSafir said:
Not being able to mount the filesystem natively in Windows might present occasional inconveniences but it shouldn't be a major problem as long as the Android devices can present the storage as USB Mass Storage mode. That being said, I have some issues with the Iconia when accessing the storage over USB. Namely, when I try to move files and folder off the device or delete them from Windows when attached via USB, the task often won't complete. I've worked around the problem by just doing internal moves, deletes and renames from inside Android (using ASTRO or ES File Explorer) and, if necessary, mounting the SD card directly in my Windows PC, which won't be possible anymore.
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That's actually a known problem... I usually just use a NAS for data exchange, as it has plenty of space and good speed, even on WiFi. Another way to do it would be a USB drive (2.5'' hdds tend to need more power for spin-up than they get from the internal port, though). Also, as I use Linux on all my computers, mounting EXT4 partitions is no problem for me ...
Hey folks.
I want to do a complete wipe before I switch Roms but the lack of formal SD storage scares me. If I wipe data that won't touch my 'sdcard' folder? Also if I want to access the filesystem via USB to do some cleaning before I wipe and also to backup my files can I do that graphically or is adb my only option?
jewnersey said:
Hey folks.
I want to do a complete wipe before I switch Roms but the lack of formal SD storage scares me. If I wipe data that won't touch my 'sdcard' folder? Also if I want to access the filesystem via USB to do some cleaning before I wipe and also to backup my files can I do that graphically or is adb my only option?
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Click to collapse
Do it graphically in android before you wipe.
If I recall correctly wiping data does not affect /sdcard
On a side note learning basic adb will save you even if you do wipe your sdcard and have a non booting rom
Sent from my Nexus 7
I can do basic push/pull stuff.. just easier with gui
Noob question here. I've seen several ROMs that say factory rest, wipe cache, wipe dalvik, which I've done many times on my GS3 and ROM'd over and over. I see on some of the N7 ROMs that say the same, but they add format data and format system before installing. Before I switch ROMs I just want some clarification. Would formatting data and system not wipe the ROM I've downloaded as well as all other data on the device? Am I incorrect in my assumption that formatting will completely wipe everything clean?
Thanks for any help from those that know.
Factory reset is just fine. It wipes data while leaving data/media intact. Formatting data, IIRC, will also wipe data/media, which will erase your virtual sd card. As for system, that is generally taken care of by the install script, although I personally opt to wipe it prior to flashing just to err on the side of caution.
Sent from my Nexus 7 using Tapatalk HD
+1 najaboy's response
You generally do NOT want to "wipe data", as that destroys the pseudo- SD card, which is where you've got all your device backups. Got those backups elsewhere?
"wipe dalvik" or "wipe cache" are superfluous because:
(a) the dalvik-cache area is in the portion of the /data partition that gets wiped by the "Factory Reset" selection. *1
(b) the /cache partition also gets wiped with the "Factory Reset" *1, *2
A lot of the "wipe this, wipe that" instructions persists in ROM installation instructions for cargo cult reasons, and also because devs for prior generations of Android releases may have provided customizations such as symlinking to move the dalvik cache onto ext partitions of external SD cards and so forth. (In that case if you wiped /data first before dalvik-cache, the symlink would disappear, and if the freshly-installed ROM also used the same trick... you would be restarting a new ROM with an old dalvik-cache from a different ROM).
If you want to know what a particular ROM or other flashable .zip file is going to do, unzip the contents of folder
./META-INF/com/android/metadata/
from that ROM/flashable .zip and have a look at the updat*-script file from that folder. It's a plain text file - open it in wordpad or notepad.
Even if you are a non-programmer, you will be able to immediately see what wipes are being performed.
In general, the installer script for full ROM installs will wipe the /system partition explicitly, whereas add-on or update packages will not.
Since there is no guarantee that a inexperienced ROM developer won't do something like wiping (all of) /data, it's not unreasonable for you to look at installer scripts before you use them. You will find that some devs are sloppier than others with things like missing assert() conditions and so forth.
*1 For TWRP anyway; I haven't used CWM for the N7 yet, so I won't vouch for that one.
*2 Note that if a Stock recovery is in use, iirc the "Factory Reset" procedure wipes all of /data - including your pseudo-SD card. So it's definition of "Factory Reset" is different from that of TWRP. Beware; Make backups!
bftb0 said:
+1 najaboy's response
You generally do NOT want to "wipe data", as that destroys the pseudo- SD card, which is where you've got all your device backups. Got those backups elsewhere?
"wipe dalvik" or "wipe cache" are superfluous because:
(a) the dalvik-cache area is in the portion of the /data partition that gets wiped by the "Factory Reset" selection. *1
(b) the /cache partition also gets wiped with the "Factory Reset" *1, *2
A lot of the "wipe this, wipe that" instructions persists in ROM installation instructions for cargo cult reasons, and also because devs for prior generations of Android releases may have provided customizations such as symlinking to move the dalvik cache onto ext partitions of external SD cards and so forth. (In that case if you wiped /data first before dalvik-cache, the symlink would disappear, and if the freshly-installed ROM also used the same trick... you would be restarting a new ROM with an old dalvik-cache from a different ROM).
If you want to know what a particular ROM or other flashable .zip file is going to do, unzip the contents of folder
./META-INF/com/android/metadata/
from that ROM/flashable .zip and have a look at the updat*-script file from that folder. It's a plain text file - open it in wordpad or notepad.
Even if you are a non-programmer, you will be able to immediately see what wipes are being performed.
In general, the installer script for full ROM installs will wipe the /system partition explicitly, whereas add-on or update packages will not.
Since there is no guarantee that a inexperienced ROM developer won't do something like wiping (all of) /data, it's not unreasonable for you to look at installer scripts before you use them. You will find that some devs are sloppier than others with things like missing assert() conditions and so forth.
*1 For TWRP anyway; I haven't used CWM for the N7 yet, so I won't vouch for that one.
*2 Note that if a Stock recovery is in use, iirc the "Factory Reset" procedure wipes all of /data - including your pseudo-SD card. So it's definition of "Factory Reset" is different from that of TWRP. Beware; Make backups!
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Click to collapse
Wow. Thanks for the very informative response. I will start looking deeper into the ROMs I'm interested in. :good:
crjjr said:
Wow. Thanks for the very informative response. I will start looking deeper into the ROMs I'm interested in. :good:
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Click to collapse
Here's one of the ROMs that says to format system and data. It's the MMuzzy ROM....
http://forum.xda-developers.com/showthread.php?t=2043869
najaboy said:
Factory reset is just fine. It wipes data while leaving data/media intact. Formatting data, IIRC, will also wipe data/media, which will erase your virtual sd card. As for system, that is generally taken care of by the install script, although I personally opt to wipe it prior to flashing just to err on the side of caution.
Sent from my Nexus 7 using Tapatalk HD
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i don't know but correct me if im wrong, coz last time on my sgs captivate days, i used to flash all kinds of rom, then there is this rom that i tried to flash that requires to format system, so i tried that rom and format system in cwm.. then when it bootup my imei messed up! i do not know if thats the reason but after that incident, i never format system anymore, just playing with wipe cache/dalvik factory reset and format sdcard in cwm works fine..
Sent from my Nexus 7 using xda premium
Excuse my ignorance, i have searched around and not found an answer to this question.
I primarily use an S3 i9300, but have bought 2 N7s for the kids.
When i install a rom on the S3, i wipe etc before doing so. BUT, the roms, kernels etc i put on my external SD car so they won't be wiped.
So, my question since the N7 does not have an external SD, where do i put roms, kernels etc so they won't be wiped?
Is it as simple as putting them in the /sdcard directory using rootexplorer?
Thanks in advance.
The "factory reset" procedure in TWRP uses file deletion rather than filesystem destruction/recreation to clean up /data - it does this in order to avoid deleting any files in /data/media (which is where the pseudo-SD card mount point lives @ /data/media/0)
I suppose CWM does the same, but I haven't used it yet, so don't quote me on that.
(Note that the STOCK recovery does in fact wipe everything though!)
Anyway, the "clean flash" procedure is to perform in the custom recovery:
- factory reset
- flash ROM of your choice
This avoids destroying stuff like ROMs and backups.
Having said that, if your tablet is at risk from random button pushing, the risks of wiping everything are quite a bit higher than when a real external SD card is used. For instance, TWRP's touch Wipe sub-menu has a button labeled "Format Data". This menu button does exactly what it says: destroys the entire filesystem in /data and initializes a new ext4 filesystem - destroying everything - including files in the "SD card".
good luck
Thanks for your reply.
I am using twrp not stick or cwm.
Great stuff learning all over again after having to do it with the s3!
Sent from my GT-I9300 using xda premium