Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.mobile.android > #56997 > unrolled thread

format on SD card?

Back to article view | Back to comp.mobile.android

Contents

  format on SD card? Eli the Bearded <*@eli.users.panix.com> - 2018-10-31 19:34 +0000
    Re: format on SD card? nospam <nospam@nospam.invalid> - 2018-10-31 15:52 -0400
      Re: format on SD card? Eli the Bearded <*@eli.users.panix.com> - 2018-10-31 20:51 +0000
        Re: format on SD card? nospam <nospam@nospam.invalid> - 2018-10-31 16:59 -0400
          Re: format on SD card? "Carlos E.R." <robin_listas@es.invalid> - 2018-10-31 22:53 +0100
      Re: format on SD card? "Carlos E.R." <robin_listas@es.invalid> - 2018-10-31 22:59 +0100
    Re: format on SD card? "NY" <me@privacy.net> - 2018-10-31 19:52 +0000
      Re: format on SD card? "Carlos E.R." <robin_listas@es.invalid> - 2018-10-31 22:56 +0100

#56997 — format on SD card?

I put an SD card into one of my android devices (6.0) and let the
system format it as native or whatever the system calls it. This
worked fine. 

Later I shut the device down, pulled the SD card out and tried to
mount it on Linux. Surprise, the format isn't recognized out of the
box and 'file -s' isn't giving me hints about the filesystem type.
Can I mount this? What should I be installing?

At the same time, I used dd[*] to copy the SD card to a new one of the
same size. I put the new one in the device and restarted, and found
that Android decided it was a blank disk and reformatted it. How can
I duplicate a SD card so that Android is happy with the copy?

[*] dd if=/dev/sdb of=/dev/sdc bs=16k iflag=fullblock conf=noerror \
	count=$COUNT
    where $COUNT is how many 16k blocks fit in 64 gigs.

This whole exercise was prompted by the original SD card starting to
give me errors.

Elijah
------
has a separate backup of the files as seen from userspace

[toc] | [next] | [standalone]

#56998

In article <eli$1810311523@qaz.wtf>, Eli the Bearded
<*@eli.users.panix.com> wrote:

> I put an SD card into one of my android devices (6.0) and let the
> system format it as native or whatever the system calls it. This
> worked fine. 

adoptable.

> Later I shut the device down, pulled the SD card out and tried to
> mount it on Linux. Surprise, the format isn't recognized out of the
> box and 'file -s' isn't giving me hints about the filesystem type.
> Can I mount this? What should I be installing?

tl;dr - no.

<https://www.androidauthority.com/high-capacity-microsd-cards-android-ga
ry-explains-690710/>
  Android 6.0 Marshmallow introduced the idea of adopting external
  storage so that it acts like internal storage. When a microSD card is
  adopted, it is formatted and encrypted to only work with that device.
  Now you can safely store both apps and private data on the card. 

<https://android.stackexchange.com/questions/137855/how-does-the-format-
as-internal-storage-feature-work-in-android-6-0>
  If you use this feature, your external SD card is replacing your
  internal storage. In the process, it will be encrypted. You no longer
  can "simply unmount" the card to read it in any other device
  (including a card reader attached to your PC), as in that case the
  file system would be unreadable in the latter (due to encryption ­
  which is done "for security", so a thief cannot simply remove the
  card to circumvent your device's lock screen and get straight to your
  data).

> At the same time, I used dd[*] to copy the SD card to a new one of the
> same size. I put the new one in the device and restarted, and found
> that Android decided it was a blank disk and reformatted it. How can
> I duplicate a SD card so that Android is happy with the copy?

crack the encryption. good luck.

> [*] dd if=/dev/sdb of=/dev/sdc bs=16k iflag=fullblock conf=noerror \
>  count=$COUNT
>     where $COUNT is how many 16k blocks fit in 64 gigs.
> 
> This whole exercise was prompted by the original SD card starting to
> give me errors.

replace it, then restore from a backup.

[toc] | [prev] | [next] | [standalone]

#57000

In comp.mobile.android, nospam  <nospam@nospam.invalid> wrote:
> Eli the Bearded <*@eli.users.panix.com> wrote:
>> Can I mount this? What should I be installing?
> tl;dr - no.
> <https://www.androidauthority.com/high-capacity-microsd-cards-android-gary-explains-690710/>
>   Android 6.0 Marshmallow introduced the idea of adopting external
>   storage so that it acts like internal storage. When a microSD card is
>   adopted, it is formatted and encrypted to only work with that device.
>   Now you can safely store both apps and private data on the card. 

Ah, okay.

>> At the same time, I used dd[*] to copy the SD card to a new one of the
>> same size. I put the new one in the device and restarted, and found
>> that Android decided it was a blank disk and reformatted it. How can
>> I duplicate a SD card so that Android is happy with the copy?
> crack the encryption. good luck.

I don't think I should need to crack the encryption to do a block level
copy of one card to another:

>> [*] dd if=/dev/sdb of=/dev/sdc bs=16k iflag=fullblock conf=noerror \
>>  count=$COUNT
>>     where $COUNT is how many 16k blocks fit in 64 gigs.

That copy doesn't rely on understanding the data copied. But it seems to
have *not* copied something that the device was able to use to notice
that the card was different.

Elijah
------
has used dd to copy harddrives to images and mounted those years later

[toc] | [prev] | [next] | [standalone]

#57001

In article <eli$1810311645@qaz.wtf>, Eli the Bearded
<*@eli.users.panix.com> wrote:

> >> At the same time, I used dd[*] to copy the SD card to a new one of the
> >> same size. I put the new one in the device and restarted, and found
> >> that Android decided it was a blank disk and reformatted it. How can
> >> I duplicate a SD card so that Android is happy with the copy?
> > crack the encryption. good luck.
> 
> I don't think I should need to crack the encryption to do a block level
> copy of one card to another:

apparently it's tied to something unique about the card, which is a
good thing from a security standpoint.

[toc] | [prev] | [next] | [standalone]

#57009

On 31/10/2018 21.59, nospam wrote:
> In article <eli$1810311645@qaz.wtf>, Eli the Bearded
> <*@eli.users.panix.com> wrote:
> 
>>>> At the same time, I used dd[*] to copy the SD card to a new one of the
>>>> same size. I put the new one in the device and restarted, and found
>>>> that Android decided it was a blank disk and reformatted it. How can
>>>> I duplicate a SD card so that Android is happy with the copy?
>>> crack the encryption. good luck.
>>
>> I don't think I should need to crack the encryption to do a block level
>> copy of one card to another:
> 
> apparently it's tied to something unique about the card, which is a
> good thing from a security standpoint.

There is a serial number on hard disks. "hdparm -i [or -I] /dev/sdX"
(Linux) can print it. I don't know if mem cards have this, too.

-- 
Cheers, Carlos.

[toc] | [prev] | [next] | [standalone]

#57012

On 31/10/2018 20.52, nospam wrote:
> In article <eli$1810311523@qaz.wtf>, Eli the Bearded
> <*@eli.users.panix.com> wrote:
> 
>> I put an SD card into one of my android devices (6.0) and let the
>> system format it as native or whatever the system calls it. This
>> worked fine. 
> 
> adoptable.
> 
>> Later I shut the device down, pulled the SD card out and tried to
>> mount it on Linux. Surprise, the format isn't recognized out of the
>> box and 'file -s' isn't giving me hints about the filesystem type.
>> Can I mount this? What should I be installing?
> 
> tl;dr - no.
> 
> <https://www.androidauthority.com/high-capacity-microsd-cards-android-ga
> ry-explains-690710/>
>   Android 6.0 Marshmallow introduced the idea of adopting external
>   storage so that it acts like internal storage. When a microSD card is
>   adopted, it is formatted and encrypted to only work with that device.
>   Now you can safely store both apps and private data on the card. 
> 
> <https://android.stackexchange.com/questions/137855/how-does-the-format-
> as-internal-storage-feature-work-in-android-6-0>
>   If you use this feature, your external SD card is replacing your
>   internal storage. In the process, it will be encrypted. You no longer
>   can "simply unmount" the card to read it in any other device
>   (including a card reader attached to your PC), as in that case the
>   file system would be unreadable in the latter (due to encryption ­
>   which is done "for security", so a thief cannot simply remove the
>   card to circumvent your device's lock screen and get straight to your
>   data).

Interesting.

Let me see if I understand right.

If it is "adoptable" the total space available is the sum of the
internal and external spaces, but in the second type the external card
replaces the internal - I hope that the content of the internal gets
copied first to the external, so that apps will work?

-- 
Cheers, Carlos.

[toc] | [prev] | [next] | [standalone]

#56999

"Eli the Bearded" <*@eli.users.panix.com> wrote in message 
news:eli$1810311523@qaz.wtf...
> I put an SD card into one of my android devices (6.0) and let the
> system format it as native or whatever the system calls it. This
> worked fine.
>
> Later I shut the device down, pulled the SD card out and tried to
> mount it on Linux. Surprise, the format isn't recognized out of the
> box and 'file -s' isn't giving me hints about the filesystem type.
> Can I mount this? What should I be installing?
>
> At the same time, I used dd[*] to copy the SD card to a new one of the
> same size. I put the new one in the device and restarted, and found
> that Android decided it was a blank disk and reformatted it. How can
> I duplicate a SD card so that Android is happy with the copy?
>
> [*] dd if=/dev/sdb of=/dev/sdc bs=16k iflag=fullblock conf=noerror \
> count=$COUNT
>    where $COUNT is how many 16k blocks fit in 64 gigs.
>
> This whole exercise was prompted by the original SD card starting to
> give me errors.

My phone (Samsung Galaxy S7) formats its cards as exFAT, and I have 
successfully copied a failing card to my Windows PC's hard disk and then 
from there to a new card.

I wonder if your Linux box doesn't have the add-on installed that gives 
exFAT compatibility. 

[toc] | [prev] | [next] | [standalone]

#57011

On 31/10/2018 20.52, NY wrote:
> "Eli the Bearded" <*@eli.users.panix.com> wrote in message
> news:eli$1810311523@qaz.wtf...
>> I put an SD card into one of my android devices (6.0) and let the
>> system format it as native or whatever the system calls it. This
>> worked fine.
>>
>> Later I shut the device down, pulled the SD card out and tried to
>> mount it on Linux. Surprise, the format isn't recognized out of the
>> box and 'file -s' isn't giving me hints about the filesystem type.
>> Can I mount this? What should I be installing?
>>
>> At the same time, I used dd[*] to copy the SD card to a new one of the
>> same size. I put the new one in the device and restarted, and found
>> that Android decided it was a blank disk and reformatted it. How can
>> I duplicate a SD card so that Android is happy with the copy?
>>
>> [*] dd if=/dev/sdb of=/dev/sdc bs=16k iflag=fullblock conf=noerror \
>> count=$COUNT
>>    where $COUNT is how many 16k blocks fit in 64 gigs.
>>
>> This whole exercise was prompted by the original SD card starting to
>> give me errors.
> 
> My phone (Samsung Galaxy S7) formats its cards as exFAT, and I have
> successfully copied a failing card to my Windows PC's hard disk and then
> from there to a new card.
> 
> I wonder if your Linux box doesn't have the add-on installed that gives
> exFAT compatibility.

The "file" command should still recognize and print the information
about the type, unless the version is too old - I think.

More likely nospam is correct about it being "adoptable" or "as internal
storage".

-- 
Cheers, Carlos.

[toc] | [prev] | [standalone]

Back to top | Article view | comp.mobile.android

csiph-web