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Hello,
Complete noob here and I am not ashamed to admit it. I did create a bootable sd card with CM7 stable on it and the card is partitioned into 4 spaces. The boot space only has a capacity of 117.63 MB, while the 4th partition named CM7 SDCARD has a whopping 28.21GB available.... 112.14MB used..... Im guessing for application. Anyways, I am trying to put books and videos on my NC and there is not enough space that is accessible. Any way to make that boot partition spave larger? Maybe move some of the extra space from the 4th partition? I have EASEUS Partition Master but I have been unable to get it to work..... Any help is greatly appreciated.
I did search for a post like this but did not find any answers which I understood.
Thanks in advance,
What is it that you are trying to do?
Homer
I am trying to put books on my sdcard that I downloaded on my computer for school. When I copy to the directory boot/myfiles/books it says that there is not enough space. So I want to enlarge the size of the boot partition
After you burn the partition image using Win32Image, the size of the boot partition is roughly 117mb. At this point use EASEUS partition to expand the boot partition to the size you want. In my 32gb SD card, I created a 16gb partition. Then I copied CM7.1 and Gapps to the partition, booted NC and CM7.1 was set up in the remaining space, with /data at 5gb and /media at 9gb.
Would you then access the files while booting from the SDcard or internal memory (eMMC)?
If you want to see them when booting from SDcard, don't put them on /boot as you have found out there is not much room. You want them on partition 4. Remember that Windows will not mount partition 4 without some heroic efforts. I use either NookColor UMS (free, see here) or WiFi Explorer Pro (paid, check either Android or Amazon Market).
If you want to see them when booting from eMMC, that is slightly more advanced. You don't have to root, but there is a file on the system on eMMC that needs to be edited to mount partition 4 rather than partition 1. It would take some time to search for it, but someone posted a guide a while back. Search for something like sharing SDcard and/or editing vold.
Homer
Ok...... So I got the boot partition resized to around 20gb and I have copied the books from my hd to the sd card E:\My Files\Books...... Problem is I now cannot acess them when I boot CM7..... Any fix to this or will I have to boot from the eMMC?
Ok....
You're making the easy stuff hard...
You want a large partition that is accessible by CM7 running off the SD and your windows PC. Like Homer said, it is nigh impossible to get windows to mount secondary partitions off of an SD card reader. What he forgot is that CM7 allows you to access partitions 3 and 4 over USB. CM7 can access the boot partition but most apps won't look there and it won't be accessible over USB.
I would recommend that you restart from scratch. Allow verygreens installer to set up the default partitions. Plug your device into your PC and transfer your pdfs to partition 4 that-a-ways. That way you won't have to remove the sd card anytime you want to access your pdf folder.
Even when you plug the CM7 booted NC into your PC, you still need to mount the /sdcard partition to Windows. I find it is easiest to use NookColorUMS on the NC to mount that partition, see above. Otherwise, when you plug into the Windows machine you only get /boot mounted.
Homer
Homer_S_xda said:
Even when you plug the CM7 booted NC into your PC, you still need to mount the /sdcard partition to Windows. I find it is easiest to use NookColorUMS on the NC to mount that partition, see above. Otherwise, when you plug into the Windows machine you only get /boot mounted.
Homer
Click to expand...
Click to collapse
Hmm, when I plugged a nook running CM7 from SD card, I get access to /media and /sdcard. I had to move the gapps.zip from /sdcard to /boot manually using a file explorer.
I'm offering an apology to gall and Homer first so pls don't jump on me.
You guys harden a simple issue and confusing the OP.
To OP,
I assume you got a 32GB uSD card, using verygreen's image. You got 117MB on boot.
LEAVE the boot partition ALONE. The only thing you should put there are the ROM (CM7 zip file) and the GApp zip file. NOTHING ELSE. Your music/ebook/video, etc. should NEVER go there. You will place them in the left-over storage created by CM7, normally called CM7SDCARD.
How do you access CM7SDCARD so that you can transfer files over?
The only way is
+ NC on
+ connecting NC to PC (windows)
+ look at the NC notification bar, usb icon should be displayed
+ tap on it, enable usb mass storage (connect to PC for file transferring....)
+ Windows PC should by now recognized the CM7SDCARD and ready for use.
That's the ONLY WAY and the correct way.
If you use that bootable CM7 uSD and plug directly into PC, you only see the boot partition which only 117MB. Again, the boot partition is NOT meant for personal stuff.
What may confuse some people is that when they plug the device into PC then it does not by default auto-mount so you don't get a drive in the PC until you use the USB notification and turn on USB storage.
For non-techie users I normally install the automount USB app from JRTStudio so the drive pops up straight away on the PC and there is no confusion over this point.
The other good reason for using the USB (or alternatively wireless connections like ES File Explorer) is that it reduces taking the SD card in and out and any risk of damaging the socket.
My apologies, I never checked out the USB notification. I sort of ignored it. It seems a handy implementation of the basic functionality of NooKColorUMS.
What is MyNOOKColor though? CM7 SDcard is the one I typically use. Nevermind: it is the eMMC. I never bothered with that one since going to SDcard boot.
Homer
Hi,
First off if this is answered I am sorry.
I did a lot of searching and was unable to see the answer to this...
I am running CM7.1 off uSD. Install went well, and have no issues. That being said, I am unable to find out where on the card to sideload books. I have booted into CM7.1, turned on USB storage, and have 2 drives appear in win: MYNOOK and CM7 SDCARD. I used the size agnostic image, and it appears that there is only the single partition on the card, and in file explorer, it shows the correct card size for memory, but only the single partition.
The only folders appearing on the card are:
.android_secure
Android
LOST.DIR
I tried to manually copy the books, media, etc. folders into a My Files folder on this drive, without success.
There is no other partition to repartition (shouldn't have to do that with size agnostic?). I have no problem loading books into the MYNOOK book folder, which I assume is the internal device memory.
Here is my question. How/where do I sideload books to use the storage on the uSD card? Do I have to create the folders somewhere? If so where?
My goal is to utilize the storage available on the card, but be able to read the titles in the stock software. Is it possible to do this without rooting, or do I need to root for any reason to access the right folders on the card for storage?
THANK YOU ALL!!
klewlessnoob said:
I tried to manually copy the books, media, etc. folders into a My Files folder on this drive, without success.
Click to expand...
Click to collapse
In what way was it not successful? Did the files copy and just can't find them with a reader? If so which reader?
The book I transferred over was not found in the stock software when I opened my library. Is there somewhere specific I am supposed to place it on the card for the Nook to see it? Thanks!
For the stock reader, I think you must use the 1gb area of the internal memory drive, which shows up as a separate drive on your PC when you plug it into the computer. When you are in CM7 and connect to the pc, cancel when it tries to install a device for the NC. Check the notifications on the NC, you need to click a button to enable copying files from your pc, and take care to properly safely remove/eject before disabling that and disconnecting the cable from your pc. Better to get a separate reader and install it from the market (e.g., Cool Reader). You can also install the Nook app from the market, but then books need to go within (possibly in a specific subdir) of the "Nook" folder on SDCARD.
So there is no way to use the card memory to store books if I want to use the stock reader??
Should there have been a "NOOK" folder created on the SD card as part of the CM7 process? Is that a file that the user needs to create? If so, does it go in the same partition as the CM7, as that is the only partition my machine is able to see?
thanks again
Hopefully you'll get more input on this, but I think the point of keeping the Nook stock available (aside from not voiding your warranty) relates to use of B&N books. However you can eject your CM sd card and use another sd card if you want more space for user media for use with the stock app. I thought the media drive was the 1gb area, but now I'm not so sure because on mine the MYNOOK disk is much smaller.
When you are in the stock firmware... you are seeing the boot partition of the uSD...
You can write the boot partition... resize it... then run the installer...
I have done it in the past... set up a 2GB boot partition... then setup the ROM on uSD. You then have a 2GB partition you can use when in stock.
Thanks for the info. I am a bit confused by your suggestion, can you please offer a bit more?
By writing the boot partition, then resizing it, does that mean I can resize now, after I have already set everything up? If so, what do you mean by the installer? Or do you mean I have to wipe the card and start over? If that is the case (start over) do you mean wipe the card, create a small partition for the boot to install on? Would that requre the use of an image that is not size agnostic?
Either way, how do I get the file structure in place on the non boot partition for the nook to see files that are saved there?
Thanks again for any help you can provide!
I have never had luck resizing it after it has been booted in the Nook and all the partitions created...
I have written the size agnostic image to the card... resized the only partition created at that point... then put the ROM on it and booted it in the nook so the installer script (size agnostic recovery) can do the partitioning and install the ROM.
For the question of getting the file structure... I'd have to ask how you wrote the files on the uSD... were you CM or stock?
I had always planned on running cm from the card, so when I wrote the files to the card, I was stock.
If I follow what you are saying, then steps for me to try at this point would be:
1. Reformat card
2. Write the disk image to the card
3. Shrink the single partition on the card (where the image is)
4. Add the CM ROM to same partition as the image
5. Install card and boot device
If this sounds right, I have 2 questions.
What size should the partition be for the image and CM ROM, maybe 2GB?
Will the Nook "see" the non-CM partition and create the file structure for saving files on the 2nd partition at some point? In my searches I saw that in early versions, there was a requirement that the 4th partition on the card be expanded to use for storage, won't I only have 2 at this point?
Thanks again so much for the help!
When you write the image to the card... it will only be about 114 MB.... you will probably want to increase the size to avoid any possible size issues later (with ROM's getting larger)
If you plan to use the stock nook ROM as well as CM7... you will probably want 2 GB boot partition... otherwise if you plan to only run CM7 you probably only want about 250 MB.
You can modify vold.fstab on the stock ROM to use partition 4 of the SD for its SD use... then you could avoid the 2 GB boot partition.
What happens when you use VG's SASD... the boot image is about 114 MB... when you boot it in the nook it creates partitions 2, 3 and 4... 2 and 3 are ext3 partitions, partition 4 is fat... partition 4 is the one set for sdcard in the ROM booted from SD...
This is why you can modify stock vold.fstab to point to partition 4... then both ROM's will be putting stuff on the same partition for "SD Card"
I think I follow that, but my issue is that currently I am unable to see partition 2,3 or 4 which I think is part of my problem.
When I set up the card, I used the SASD method, and all I can see in both win explorer and partition software is the single partition on the card. Should there also be partitions 2,3, and 4? Do I have to do something to make those partitions viewable?
I am not comfortable enough with my skill level to attempt to modify the stock vold.fstab file on the device, and was hopeful that by properly setting up the card, I would be able to keep stock as is, and use the card to multipurpose, ie run cm7 on part and use the remaining space on card to store books to be read in stock firmware. I am still hoping to do that....thanks
As far as only seeing partition 1.... that is a limitation of Windows.
By following the advice pertaining to starting over and increasing the size of the Boot partition immediately after writing the image... before doing anything else... you can provide more space for the stock ROM to use on the SD... it will use partiton 1 (the boot partition) without the other modifications to vold.fstab
ok, confused again
If I start over, write image, then resize that partition with the image, am I going to use the "rest" of the card, NOT in that partition to use with storage? OR am I going to resize the partition with the image to be big enough to use as the partition to put books on?
If it is the former, don't I again run into the problem of how to find the other partitions, or will I create them when resize the first partition after writing the image?
Thank you!
You will only ever see the first partition of the sd card when booting from the stock OS. Also with the card inserted in a usb flash card reader on Windows you can only mount the first partition as a drive letter. But you can see and resize partitions with contiguous unallocated space using MiniTools Partition Wizard.
OK thats good to know. Do you know if the SASD install should have created other partitions when I installed to the card? The reason I ask is that even in Partition Wizard, I am still only able to see the 1 large partition with everything in it.
If I start over again, will I need to use the wizard to create partitions first, then write the image to the resized 2 GB first partition, or should I write image to card, resize the first partition? If the latter, will resizing the first partition autmatically force the other partitions to be seen? I am not sure of this option, as I can't see where in the process the other partitions are created? Is this part of the process when CM7 boots?
Thanks!
Write the image. Safely remove from pc. Reinsert to pc. Use minitool partition to resize the (only, at that point) partition to the size you want. Use Apply in minitool software. Quit minitool and resume with the card setup.
does the minitool at that point (resizing) create the other partitions, or will the card setup do that? Do I have to do anything else to the other partitions to make them visable to the stock nook so that they can be used to access books while in stock os?
The card setup will create the other partitions. The stock os is never going to see anything but the 1st partition. You would need a terminal emulator or rooted file explorer installed in the stock os in order to mount another partition.
If that is the case, that stock os will never see anything other than the 1st partition, then there really is no way to accomplish what I am trying to do, correct?
In other words, put CM7 on the card, then when I want to use stock, boot into stock and have the reader find books saved on the card?
This is completely pulled off of my other thread in the HOX+ section
our device is a data/media device which is why usb mount don't work
here's a link that explains it all
http://teamw.in/DataMedia
and part of the convo with dees_troy is below
<Dees_Troy> Nope, it will *never* work on a data/media device
<Dees_Troy> read and learn: http://teamw.in/DataMedia
<WinBot> [Link] http://tinyw.in/lstO :: What is a data media device? | TeamWin
<Dees_Troy> definitely worth understanding
<Dees_Troy> at some point we're going to try to kang in MTP for recovery
<Lloir> so for now then it's sideload or from inside the rom
<Dees_Troy> or adb push
<Lloir> aye
<Dees_Troy> or gtfo
<*****> so cant mount usb storage with newer devices...hmm one x did guess this is where confusion at least on my part came to be
<Lloir> lmao Dees_Troy
<Dees_Troy> one x wasn't a data media device
YOU MUST either transfer the rom\boot\porn\audio\mods while the phone is on or use adb push or even sideload when in recovery, THIS IS THE ONLY way
IF you want to read without clicking the link i'll whack it up in #2
What is a data media device?
I'm writing this page because there seems to be a lot of confusion about how many of the newer Android devices work. Starting in Honeycomb 3.0 with the Xoom, Google changed the way that they handled storage. Instead of having a "data" partition with your apps and a separate "sdcard" partition for storage, Google started giving you a single, very large data partition. Inside /data is a folder at /data/media that contains all of the contents of what you think of as your internal sdcard.
Since /data/media is part of /data, we pretty much never actually format the data partition. Formatting data, of course, also removes the media folder that contains the internal sdcard. When you choose a factory reset, instead of formatting, we use rm -rf commands to remove all the folders except for the media folder so that we can remove all of your apps and settings while leaving your "sdcard" intact. In TWRP we also have a wipe internal storage option that rm -rf's the media folder and a "Format Data" option that formats to recreate the entire file system in case something goes completely wrong or to remove device encryption.
When you're booted to Android, Android fuses the media folder to /sdcard and emulates a FAT files system that doesn't have permissions for legacy apps. We don't currently have fuse in recovery, so we just add an extra mount command to mount /data/media to /sdcard so in recovery you still have to worry about permissions on /sdcard.
Because the "internal sdcard" is not a true FAT file system, you can't mount it via USB storage. Well, that's not technically true, but the vast majority of people use Windows computers and Windows doesn't recognize ext4. If we were to allow you to mount the data partition via USB storage, Windows would claim that the device wasn't formatted and offer to format it for you, which, as you can imagine, would be a disaster. The whole ext4 setup is another reason that Android switched to using MTP for transferring files. Most of these devices don't have the necessary kernel configuration to even support USB storage mode, so it's not very easy to enable USB storage if we even wanted to try. Unfortunately at this time, MTP isn't available in recovery, so if you have no other option, you will have to use adb to push and pull files to/from your device.
As a special note, if you choose to do a factory reset from your ROM, even if the ROM says that it will wipe everything including the internal storage, well, that's not what TWRP will do. A stock AOSP recovery would format data including the "sdcard" but TWRP will use its regular factory reset setup that leaves the internal storage intact.
There are a couple of nice gains with using this setup vs the old data + FAT storage partition. With /data/media you, as the user get more control over how you use your storage. If you have a ton of apps, then that's no problem since you have a huge data partition to work with. If you don't have a lot of apps, you get more room to use for storing things like movies. Further, ext4 doesn't suffer from the 4GB file size limit that FAT has, so you can have a large, high-def movie on your device if you like. I'm sure another motivating factor was to get Android away from using FAT which is a Microsoft creation. Performance on ext4 in Android is also probably better than FAT. As a downside, data media devices tend to store a lot more app data in the "data" section and so backups on these devices tend to be larger.
Thank you for this post. I had been a bit curious about this. I have Evo LTE. But I also Boughy a family member a GNex that I have to maintain. I know that my Evo, I can plug into windows, and when I select USB transfer (not in recovery), it mounts my internal storage (not ext_SD) , and it shows as removable drive in windows. But,....when I plug in GNex, it shows up as GNex , not removable drive H. I always wondered a bit about what this all means.
Thanks for the info. :thumbup:
Sent from my EVO using xda premium
Thanks for the useful post.
If I make a nandroid backup for the whole device, will it exclude the /data/media folder? Because on my old phone the nandroid backup doesn't include /sdcard.
romitkin said:
Thanks for the useful post.
If I make a nandroid backup for the whole device, will it exclude the /data/media folder? Because on my old phone the nandroid backup doesn't include /sdcard.
Click to expand...
Click to collapse
Yes it does, we are past the point where that causes issues.
Everyone just needs to get used to the data/media thing. And learn how to use adb side load
I predict a whole bunch of "bricks" due to people not informing themselves on how the phone works and how to use adb
Sent from my One X using Tapatalk 2
A little bit from my side as well I hope someone will find this helpful. Virtual SD card on Android
Can't you use USB Host if you got recovery installed as well? I think I've read that somewhere...
mike1986. said:
A little bit from my side as well I hope someone will find this helpful. Virtual SD card on Android
Click to expand...
Click to collapse
Link broken, here is the correct URL:
http://android-revolution-hd.blogspot.com/2013/03/virtual-sd-card-on-android.html
Oh and bump for anyone new to the idea of a "data/media" device. You're not in Kansas anymore.
NxNW said:
Link broken, here is the correct URL:
http://android-revolution-hd.blogspot.com/2013/03/virtual-sd-card-on-android.html
Oh and bump for anyone new to the idea of a "data/media" device. You're not in Kansas anymore.
Click to expand...
Click to collapse
Lloir, thanks for sharing and good explanation. MTP makes sense and on my One, this way file transfers are simple and fast. However there are two things I dislike about MTP right now:
When you copy files to the device, on some file types it throws a warning that the device might not be able to read the file. This interrupts the file transfer and I have to confirm I want to copy the file to the device. On an older MP3 player I have, I could deactivate this by editing a device capabilities XML file. On the One, I did not find such a file. Perhaps an option in the MTP deamon?
When I am transferring files, I can't browse through other folders at the same time. It says the device is busy.
Is there a way to solve those two issues or "is it what it is"?
Lloir said:
Windows would claim that the device wasn't formatted and offer to format it for you, which, as you can imagine, would be a disaster
Click to expand...
Click to collapse
I did that on a device. Windows offered to format and I did it. Man that was not good! 2 hours later after manually restoring the partition values I was OK and the most amazing thing all my data was there perfect and untouched :silly: :highfive:
Thanks for that great explanation. Been having some issues with windows and android. Nothing big just had to sideload my ROM and killed my "sdcard" at least now I know why
Note from the Author -
I am moving on to the N5 now and ditching my S3. I will continue to maintain this thread, however - please do PM me if you think that something needs to be changed or updated in this thread as I doubt I will be answering questions within the thread as much. Please don't PM support questions to me. Only PM updates that need to be made in the thread.
It's been a blast!
Regards
Dan
S3 Storage (Data Loss Recovery / Prevention / Info)
This thread is intended to give you an overview of some of the Storage of the S3 from a Data Loss and recovery perspective. It is not intended to cover USB sticks or mods to Swap / Mount other storage. It is solely to cover day-to-day data concerns and give a background to how these things work
Please note, if you have recently swapped between Android 4.1 and 4.2 and cannot find your sdcard data, you need to read [Info] Flashed 4.2? Can't find your /sdcard data?
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Before we get started...
Here are a couple of threads you should get familiar with before posting on XDA.
Forum Rules - use Search before posting
Post Questions or Support queries in Q&A, NOT General
Backround of Android storage (Pre-S3)
Firstly, I think we need to understand how Android worked historically as this will help us to understand how the S3 works now.
A legacy android device, lets pretend the HTC desire on Android 2.2 as this was a standard configuration at the time. It had 2 major partitions (and several minor ones which are irrelevant to this topic). It has the /system partition and the /data partition. These were partitions of the internal NAND flash memory.
/system is where the Android operating system lives. The user could not delete or change anything in here (unless you were rooted). All the software that came with the phone was installed in the /system partition
/data is where all the userdata goes. Whenever you installed an app from the market, it installed to /data/app and it put all it's important data into /data/data. Also any system settings you changed (Wallpaper, ringtones etc) all were stored in /data/data. When you did a factory reset, it wiped /data and everything in it.
Of course, having these 2 partitions was not enough for everyday use. There was no where to store your music, photos, documents etc. /data is just for app data and settings. So this is where /sdcard comes in
/sdcard is the Android mount point for the External SD card in this legacy android device. This means that when you inserted a Micro SD card, Android used /sdcard as it's internal reference to where the card's storage is. The /sdcard was a necessity before you could take photos. Over time, bigger apps started to put other data here. For example, a GPS / Map application would store its apk (application package) in /data/app and store your personal configuration settings in /data/data but it may download and store offline maps somewhere on the /sdcard. In older devices, the internal Memory (NAND Flash) was usually too small to allow much data on it. Many users would have to root to get more storage space or keep uninstalling apps to keep the "low on space" warnings at bay
How the S3 is different
Well, the S3 is substantially different. There are of course SOME similarities. For example, the S3 still has internal NAND Flash Memory. This is often referred to as the eMMC (Embedded MultiMedia Card) - which still contains the /system and /data partitions, used in exactly the same way.
The main difference is /sdcard. The S3 is designed specifically so using an external micro sd card is NOT a necessity. It has a larger NAND Flash internal memory (eMMC) so it can also have an "internal SD card". This is where people start to get confused. The entire internal memory is an eMMC which is essentially an internal SD card, however a partition of that internal memory is /sdcard.
OK, I know - let me explain. /sdcard is a mount point that Android uses to know where to store /sdcard data. But on the S3, instead of storing it on a required external sd card, it points to an internal memory partition. Now here is the clever bit. The /sdcard actually points to /data/media (or /data/media/0 in Android 4.2 onwards). So you continue to have your /data partition, but within /data you have:
/data/app
/data/data
/data/media
The clever thing is that the file system that android uses for /system and /data is a Linux file system called Extended FS. In our case, we use the Ext 4 file system. This is important to understand because these file systems do not work with Windows so an external SD card would usually be Fat 32 file system, or exFAT so we could plug it into our windows computers and read the contents. What Samsung have had to do is use the FUSE file system to allow /sdcard (or /data/media) to exist as a FAT file system within the EXT 4 file system. Clever stuff. But it has it's pro's and cons...
You lost me at file system
All electronic systems that have an operating system and store data use a file system. Think of it in it's simplest form. Imagine a school text book. It has lots of chapters about different things. It has a "Table of Contents" in the first few pages, telling you where each chapter in the book is so if you want to know what page chapter 13 is on, you look in the contents and find the page and go straight there - The alternative is looking through each page individually to find the chapter. Not a quick process.
Well data storage works the same. When you put a file on a hard drive, sdcard, USB stick (or whatever) it is written to a specific location. When it is written to this location, the location is added to the file system. So when you put word.doc onto the drive, The file system is informed of the (very complicated) location of the file. When you tell Windows, Android (or whatever) that you want to open word.doc, the operating system consults the File system and goes to retrieve the data from its true and real (yet very complicated) location on the drive.
There are many file system types still in use today. Usually they are operating system specific. For example, Ext 4 is a Linux file system (and Android by Proxy as it is Linux kernel based) and Windows cannot read Ext file systems. Similarly, exFAT is a Microsoft file system (also used for sdcards on the S3) and cannot be used (easily) on Linux machines. Since most everyday users of the S3 are Windows users, you can see now hopefully why it was important for Sasmung to use "magic" and implement FUSE to allow an exFAT file system to be used for /sdcard, within the Ext 4 partition of /data
Did I REALLY need to know ALL that?
You know what? Probably not but it may go some way to help understand the limitations we will cover later on.
A bit more info for the S3
Obviously, the internal memory supplied with the S3 may not be enough for all users so they added the ability to add expanded memory in the form of the Micro SD card. Android uses the Mount point of /extSdCard now, instead of /sdcard like it used for legacy devices - because /sdcard is already in use elsewhere.
One thing many of you have probably noticed is that with the S3, there is no option to mount the /sdcard or /extSdCard as USB Mass storage on your computer. You must use MTP or PTP.
PTP - Photo Transfer Protocol. When you connect your S3 to your computer using PTP, Your computer sees it as a camera. It will show photos on your "camera" and will set about implementing the default camera options (such as suggesting you import your photos) etc. It won't show documents or other media necessarily.
MTP - Media Transfer Protocol. When you connect your S3 to your computer, it will be seen as a media player. This should allow you full access to all the files on there, including word documents and the such like.
One of the reasons for this is that because /sdcard points to something using the FUSE file system and is not a true partition, it would be difficult to allow it to be used as USB Mass Storage. It may or may not be possible but the biggest advantage of using MTP / PTP is that the computer and the S3 can both access the internal memory at the same time. With USB Mass Storage (UMS) this is quite awkward and can result in errors.
Deleting data
This is partially why we needed to understand a little about file systems. So I could explain to you how data is handled when it is deleted.
As I explained earlier, when you write a file to memory, a corresponding entry is written to the file system to advise the OS where the data is. Sure, you may think you are writing the file to /sdcard/documents/work directory on the internal memory, but in reality these directories or folders do not actually exist at a memory hardware level. The data is written to a block and the file system is informed where that block is, how big the file is, what directory it should appear in to the OS etc. When a file is written the memory, the OS see's the available space go down and the used space go up. All this information comes from the file system.
When you delete the file, the actual data is NOT deleted. It remains where it is on the memory. The block is not overwritten. When the OS is told by the user to delete the file, the File system entry is deleted. This changes the free/used space as the file system is no longer accounting for the data, however the truth is the data still exists. When the next request to write a file to the memory comes from the OS, the file system will think the block where the old data was is empty and will overwrite it.
It is this difference between the file system and reality that allows data to be recovered by external software. if you do not write any data to the memory, external software can scan the memory for data whilst bypassing the file system all together. Ff course the window is small. You only have a very limited time to recover data before the file system allows the data to be overwritten with a new entry.
This is not just true of a deleted file. Even formatting the memory (which is actually just re-creating a new, blank file system) leaves all the data in tact behind-the-scenes and can all still be recovered until you start writing data to the memory. Cool huh?
Wow, all this time I've been stressing, is it really that simple?
Awwww snap! You got me. No it is not that simple. All this PC software, example: Piriform recuva only works on a computer drive. In windows, imagine this is anything with a Drive Letter. C: drive etc.
The only way to get a drive letter on your sdcard is to use USB Mass Storage mode, which as previously discussed - is not possible on your S3 (unless you are rooted, you can mount USB mass storage in custom recovery or use a UMS app from Play). The alternative is to use a card reader on your PC and put the sdcard in it.
There are also apps like Undelete for root users - which again, you guessed it - requires root. So if you're not rooted, it's simplest to use a card reader which can be bought for peanuts.
It's worth mentioning, NONE OF THE ABOVE will work with /sdcard on internal memory. It is not possible to get your data back once deleted from internal memory. Once gone, it's gone forever. You can only restore from /extSdCard (removable, external SDcard)
Phone won't boot, can I get my data back from internal memory?
Let's start by saying, it depends why your phone won't boot. If it's an SDS (Sudden Death Syndrome) type issue, where your internal eMMC (NAND FLash memory) has failed, then no. However, if you believe this is not the case then you can get your /sdcard data using adb BUT you need a custom recovery to be flashed via Odin before you do this. Read [REF] Understanding the basics before rooting your S3
However, if out of curiosity - you do still want to get your data off, using adb , read below:
Pre requisite is having adb "installed" on your windows PC. Download THIS file and follow the instructions in the readme.
You need to observe the following. For android 4.1.x and earlier, /data/media for android 4.2.x and newer, /data/media/0 - I will assume 4.2.2 for this guide,.
1) Boot into recovery, connect usb and go to "mounts and storage". Toggle the "mount data" options to mount these partitions. Tip, when mounted, the option then becomes "unmount data"
2) Open "cmd" in Windows and type the below code, which will copy all your data to a folder called sdcard on your windows desktop
Code:
adb pull /data/media/0/ c:\users\rootsu\desktop\sdcard
Also note, this assumes you have windows vista or newer. Also, it assumes your windows username is rootsu.
That's it, simple.
Display and Digitiser won't work, can I get my data back from internal memory?
You can use adb and a custom recovery to pull data from your /sdcard or even app data from /data/data
Pre requisite is having adb "installed" on your windows PC. Download THIS file and follow the instructions in the readme.
You need to observe the following. For android 4.1.x and earlier, /data/media for android 4.2.x and newer, /data/media/0 - I will assume 4.2.2 for this guide,.
1) Boot into recovery, connect usb and go to "mounts and storage". Toggle the "mount data" options to mount these partitions. Tip, when mounted, the option then becomes "unmount data"
2) Open "cmd" in Windows and type the below code, which will copy all your data to a folder called sdcard on your windows desktop
Code:
adb pull /data/media/0/ c:\users\rootsu\desktop\sdcard
Other things you may want to pull.....
Code:
adb pull /data/data/com.android.providers.telephony/databases/mmssms.db c:\users\rootsu\desktop\sdcard
Code:
adb pull /data/data/com.android.providers.contacts/databases/contacts2.db c:\users\rootsu\desktop\sdcard
Also note, this assumes you have windows vista or newer. Also, it assumes your windows username is rootsu.
That's it, simple.
Data corruption
When data becomes corrupt, there's really not a lot you can do. The file system knows where the data is already. If it's corrupt, you're stuck. Most common causes of corruption are:
1) Dirty unmount of /sdcard. SD card pulled out whilst it is being written to / phone shuts off whilst being written to. SOMETIMES - Plugging the card into a card reader in windows, Windows will ask to fix it and MAY fix it.
2) Fake SD card. This is really the MOST common. Get a card reader ans use:
h2testw.exe for windows to test your card in a card reader. Set it to read the full size of the card, which will take hours but well worth it.
If you get a result like this:
Code:
Warning: Only 63995 of 63996 MByte tested.
The media is likely to be defective.
3.8 GByte OK (8072512 sectors)
58.6 GByte DATA LOST (122989248 sectors)
Details:2 MByte overwritten (4096 sectors)
...Then you have a fake card, that is really 4 GB. I'll explain this.
Commonly, fake cards are reprogrammed to "think" they are high capacity cards, such as 32 GB or 64 GB to defraud buyers out of money. This is common on eBay (Never buy cards from eBay).
When these cards are formatted, the file system also thinks it is this fake capacity. Normally, when a card is full, the file system will report to the OS there is no more space and this prevents additional writes to the card. However, in the case where the card is 4GB and the File system thinks it is 64 GB, the tricked file system doesn't know the card is full. The file system keeps allowing data to be written to the card, over writing the existing data but without replacing the file system entries. The file system thinks data that has been overwritten hasn't been overwritten so when you try to open one of these files, it is essentially "corrupt" or non-existent.
Preventing data loss
Time to wise up guys. It is possible to recover data off your removable media, but internal memory - very unlikely. No apps on your PC or Android will help with deleted data. So you need to backup.
Dropbox - Use dropbox to automatically upload your photos to online storage.
Foldersync - Use FolderSync to upload important sdcard files to your dropbox account, or better yet - got a computer thats always on at home? Set foldersync to schedule a sync over wifi whilst you're asleep.
Other info
Interesting tidbits
Quite an exhaustive reference guide you got here rootSU thanks this will sure come handy for all of us :good:
Cheers
Thank you very much for taking the time to write this. It's a non academic approach to a sum of keywords and all of them are explained in such a manner that it would be almost impossible to misunderstand
Nice!
Nice post!
There are a few other interesting tidbits of info that might be worth mentioning:
- eMMC has an internal micro-controller that runs very specific firmware (and SDS was mainly caused by a bug in that firmware)
- eMMC (just like SSD) has specific writing/erasing limits and commands to deal with that - as a very general idea it can write about 4k at a time but can only erase in much larger blocks - like 64k (at least, but a 16GB model could have a much bigger block); normally on the same erase-size block there is very special list maintained, and based on that list wear leveling is implemented;
- all flash-based memory AGES - there is only a limited amount of erase/writes cycles possible before a point where the info is no longer reliably-stored; in some models that value can be incredibly small! to avoid writing more to some regions than other a mechanism call wear leveling is implemented; that one can have a big impact on both speed and reliability (but really don't expect it to create miracles)
- since it is very important for the speed and reliability of the flash memory to return unused blocks to this internal lists there are special TRIM commands that informs the firmware that the block can be garbage-collected; with an OS that supports TRIM, when a file is erased the blocks are also TRIMmed; this is one extra level that makes recovery basically impossible under normal circumstances
- this does not really mean that things are completely impossible to recover, just that you might need to spend so much on it that recovery would be impractical for any item worth less than 100000 US$ to 1 million US$
EDIT
- also just as with SSD it is not a bad idea to keep a good percentage of the flash memory free - IMHO at least 4GB for 16GB models, 6-8GB for 32GB models - that will improve performance since fragmentation (CLARIFICATION - free-space fragmentation) will grow much slower
- unfortunately there is no program for eMMC similar to smartctl (or any other SMART-data reading program) on normal SATA/IDE/SCSI disks - there seem to be some proprietary commands that are somehow similar but those are generally undocumented.
xclub_101 said:
Nice post!
Click to expand...
Click to collapse
I've put a link to your post in post 1. Where as it's not strictly relevant to my point, it is interesting stuff....
Fragmentation isn't an issue on ssd's. Its an issue on hdd because the head must physically move to another area of the Platter to get the data. That's the slow down. Defrag of a hdd moves all the used blocks (data) together so the actuator doesn't need to move much.
Performance degrades over time on ssds because every write, if data already exists must be erased too. But this hasn't really been an issue so much since TRIM became widely available.
-----------------------
Sent via tapatalk.
I do NOT reply to support queries over PM. Please keep support queries to the Q&A section, so that others may benefit
rootSU said:
...
Fragmentation isn't an issue on ssd's.
...
Click to expand...
Click to collapse
Thank you.
Also sorry for the misunderstanding with my contraction - what I wanted to say was free space fragmentation - that one does matter a lot on solid-state memory because of the garbage collection and some controllers have been famous for having a huge drop in performance with little free space - I will try to also correct that post.
xclub_101 said:
Sorry, I used a misleading contraction - what I wanted to say was free space fragmentation - that one does matter a lot on solid-state memory because of the garbage collection and some controllers have been famous for having a huge drop in performance with little free space - I will try to also correct that post.
Click to expand...
Click to collapse
Yep, it's true about Garbage collection, but TRIM *should* handle this nicely as should "over provisioning" although probably, some cheap SSD's may not over provision.
EDIT> Actually (sorry everyone for off topic) if you're interested in SSD's, these articles are a "fun" read... (I put fun in speech marks as it depends how geeky you are )
http://en.wikipedia.org/wiki/Trim_(computing)
http://www.pcworld.com/article/2038...-ssds-what-makes-these-speedy-drives-hum.html
Update to post 1:
Note from the Author -
I am moving on to the N5 now and ditching my S3. I will continue to maintain this thread, however - please do PM me if you think that something needs to be changed or updated in this thread as I doubt I will be answering questions within the thread as much. Please don't PM support questions to me. Only PM updates that need to be made in the thread.
It's been a blast!
Regards
Dan
Awesome bits of info. This is the game changer. I learned a whole lot just by reading here in XDA. I've only been using Android for a few weeks but thanks to XDA, I've already rooted, installed a bunch of apps and kept my OCD in check.
my device memory has corrupted and when i start recovery mode i get "E: faild to mount /cash (invalid argument) "
can anyone help me please i need to retrieve msgstore.db.crypt7 from my internal memory i have rooted my phone and have omega custom rom.i accidentally deleted the whole folder using es file explorer what's app only retrieves the message back 7 days ago and i need to go back further more,i have tried undelete and digger disk both dont find the internal memory i have tried several applications but wont find my phone i have enabled usb debug mode still wont find my phone i have heard recuva works but sgs5 doesnt have usb mass storage but on my pc windows 7 it shows portable device so i can see my internal and external but not through programs can anyone help me please?
bump any help please?
If you did the smart thing i.e. turned your phone off immediately after you deleted the file, you should be able to recover it. But if you kept mucking around (in addition to not having a backup of your phone), all bets are off. You may well have overwritten the database if you continued to use the phone.
Your best bet would be to copy the area of phone memory where the database is or was. That both preserves a copy of what is recoverable and lets you avail yourself of the large number of PC based data recovery programs available.
The following terminal (CLI) commands should image (make an exact copy) of the /data and /system partitions to your external SD card. Then use a PC based data recovery program to recover the deleted file. Check these commands for typos before executing them. A typo could make a real mess of your phone's file system.
$ su
# dd if=/dev/block/mmcblk0p25 of=/extSdCard/data.img
# dd if=/dev/block/mmcblk0p23 of=/extSdCard/system.img
.
fffft said:
If you did the smart thing i.e. turned your phone off immediately after you deleted the file, you should be able to recover it. But if you kept mucking around (in addition to not having a backup of your phone), all bets are off. You may well have overwritten the database if you continued to use the phone.
Your best bet would be to copy the area of phone memory where the database is or was. That both preserves a copy of what is recoverable and lets you avail yourself of the large number of PC based data recovery programs available.
The following terminal (CLI) commands should image (make an exact copy) of the /data and /system partitions to your external SD card. Then use a PC based data recovery program to recover the deleted file. Check these commands for typos before executing them. A typo could make a real mess of your phone's file system.
$ su
# dd if=/dev/block/mmcblk0p25 of=/extSdCard/data.img
# dd if=/dev/block/mmcblk0p23 of=/extSdCard/system.img
.
Click to expand...
Click to collapse
Thanks i've tried every recovery software for android but it's not detecting any of the internal memory as sgs5 does not have usb mass storage i have enabled usb debug settings i have the samsung usb drivers but it shows up on my windows 7 as a portable device.
do you recommend any decent software or tutorial's which might help me recover it.
Thanks for your help!
xxmcvapourxx said:
i've tried every recovery software for android but it's not detecting any of the internal memory as sgs5 does not have usb mass storage
Click to expand...
Click to collapse
You didn't follow any part of what I suggested, so it's a mystery why you quoted my post. I specifically advocated using PC based data recovery software, not an android app. And at no time would you need your S5 to be in MSC (mass storage) mode.
Use the posted commands to copy your memory contents to a SD card, plug the SD card into a PC and then use a PC based data recovery app. The commands can be entered from a terminal emulator app, TWRP or an ADB shell session CLI.
Good luck
.