On 2018/10/7 下午6:39, evan d wrote:
>>> like so?:
>>> grep -obUaP "\x5F\x42\x48\x52\x66\x53\x5F\x4D" /dev/sdc
>>>
>> Yes. And it will be very slow, since you're going to read out the whole
>> disk.
>>
>> But I don't really think you would get some hit, according to current
>> result.
> 
> Ok, so it is what it is.  Based on what you're telling me, whilst the
> data may be there and intact, the superblock is irretrievably damaged
> and the data is thus for all intents and purposes lost.

Although the result is the same (data all lost), but I don't believe
it's only super block corrupted.
If you have some special magic string, like "#!/bin/bash" or "\x7f\x45
\x4c\x46\x02\x01\x01\x00" (elf header) , you could try to grep through
the whole disk.

I believe the data (or at least part of the data) is also corrupted in
this case.

> 
> I may as well use wipefs to clear crud from both drives, partition and
> format them and then use them elsewhere.   -- this more or less
> accurately summarise the situation?

Unfortunately, yes.

Thanks,
Qu

>