This is about data corruption
on android . The primary issue relates to bad blocks / clusters
and it happens to be android platform. So this is a super user
and NOT android
enthusiast question. answers to this question will apply to ANY corrupt card whether PC or android. So its thoughtless to tag this is android
This is a Sandisk 128gb ( leave this link - its not an ad .Specific card indicates other paras like memory channels , write speed etc card I am using on an Android Nougat
device.
This is the 2nd time the card had corruption issues. 1st one I bought got Write Locked . Present Replacement was provided
The card has a lot of bad clusters
. 2 things got me to sniff this :
whatsApp
directory ( which had a bind towhatsapp
dir on internal ) : the image directory can no longer be written to- Phone randomly reboots and next time
exFat
partition is not mounted ( I usedapp2sd
and partitioned the card toext4
10gb to link my apps and rest ifexfat
)
ran a chkdksk
on windows 7 and it would autoterminate on initial run & persisting on running gave me repeated message "# cluster
moved for file " ( cant recollect exact verbiage ). It could Never complete it but aborted with the message . "corruption found in card "
questions :
- How do I know if there is logical or physical bad cluster. Any tool / test ?
Here's something I did - that made me think logical. I removed the images directory ( which was write locked and so as long as the binding was on , whatsapp images could not be downloaded. Once I switched offfolder mount
tool that enforced this, it would work ) after moving the contents to dir2 and renamed dir2 to original dir. after del the original dir. Now for sometime whatsapp binding would work and the same problem came again . So I tend to think but need confirmation. - I am thinking of salvaging the contents of
exfat
partition and then format partition and instead create 2ext4
partitions ( orFF2S
. Tell me which is better) . One is for less write apps. My photos etc here and other smaller one just for whatsapp and then copy back contents to relevant partitions.
If I do this. There is no out of box support for ext4
partitions for android ( isn't ,pl confirm) ? how do I auto mount without 3rd party utils ( fstab
? )
How do I auto mount the extra ext4 - fstab
?
Will this help avoid the above problem ?
- While I still have the corrupt block partition is there ANY other tool that will run till the end and identify all bad blocks so they can be kept aside .I tried
aparted
forandroid
which runsfsck ( exFat
sub ) and the report came normal in < 1 min .
chkdsk -Drive -f
.... If a nondestructive -f won't fix it... try a destructive fix with -r (it implies -f )chkdsk -r
– Gadget Guru Mar 22 at 20:37