How can I repair [android_meta] and [android_expand] partitions?

How to use TestDisk to recover lost partition
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wrosner
Posts: 1
Joined: 27 Nov 2021, 13:38

How can I repair [android_meta] and [android_expand] partitions?

#1 Post by wrosner »

I had installed a Kingston 32GB SD as memory expansion into a Blackview 6300 mobile - Android 10 afaik.
After hard mechanic shock (presumably), I got the message "SD-Karte beschädigt" - means "SD card is damaged".

For rescue, I mounted the card to my debian 10 and performed a ddrescue backup.

testdisk (7.0 debian stock) finds

Code: Select all

Current partition structure:
 1 P Unknown                     2048      34815      32768 [android_meta]
 2 P Unknown                    34816   60751838   60717023 [android_expand]

search_part()
Disk /dev/sdc - 31 GB / 28 GiB - CHS 29664 64 32
FAT32 at 4/0/1
FAT1 : 1556-8969
FAT2 : 8970-16383
start_rootdir : 16384 root cluster : 2
Data : 16384-60743679
sectors : 60743680
cluster_size : 64
no_of_cluster : 948864 (2 - 948865)
fat_length 7414 calculated 7414
heads/cylinder 255 (FAT) != 64 (HD)
sect/track 63 (FAT) != 32 (HD)
set_FAT_info: name from BS used

FAT32 at 4/0/1
     MS Data                     8192   60751871   60743680
     FAT32, blocksize=32768, 31 GB / 28 GiB

Results
   P MS Data                     8192   60751871   60743680
     FAT32, blocksize=32768, 31 GB / 28 GiB
     
[...]
     
interface_write()
 1 P MS Data                     8192   60751871   60743680
write!
No extended partition
 
Since I could read some files, I applied the changes.
Was able to mount the remaining single partition in debian.
Plugging the card back to my mobile, it is identified as "mobile storage", the SD-Extension is marked as "missing".
A number of apps are not available any more.

It appears to me like I had removed some kind of advanced Android partition format relating to memory extension and converted the SD to a bare data storage.
Can I revert this? ddrescue?
And how can I fix the damaged [android_meta] and [android_expand], after all?

recuperation
Posts: 2720
Joined: 04 Jan 2019, 09:48
Location: Hannover, Deutschland (Germany, Allemagne)

Re: How can I repair [android_meta] and [android_expand] partitions?

#2 Post by recuperation »


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