sd4l-user

Re: [SD4L-user] Follow-up: SD4L problem -- Windows container won't mount

[Hans-Ulrich J. <han...@t-...>]

Hi Martin,

Martinveg wrote:
> Hi, Hans-Ulrich,
> 
> This is a follow-up to my previous message of yesterday:
> 
> Today I tried again to mount the container, and when it wouldn't
> mount, I followed your instructions again, doing the fsck -t vfat
> /dev/scramdisk/vol01 command. And the result appeared to be exactly
> the same as yesterday. This suggests to me that the command did not
> change my container file at all -- indeed, the notation: "Leaving file
> system unchanged" suggests this. I commanded it to correct the
> problems and delete the bad files, but it seems that it didn't do it.
> 
> How do I get it to actually make the required changes?
> 
> Thanks again,
> 
> Martin
> 

Yes that means, that the changes haven't been written.
There are a number of further options you may try.
By the command

man fsck.msdos

a manual page of the msdos/vfat file system checker,
which fsck calls with the option -t vfat, is displayed.
You can always find such man pages in the internet
if they are not installed on your computer or you
like a more friendly presentation in the browser.
Especially the options (copied from the man page)

-w for "Write changes to disk immediately."
-t for "Mark unreadable clusters as bad."
and perhaps
-a for "Automatically repair the file system.
        No  user  intervention  is necessary.
        Whenever  there  is more than one method
        to solve a problem, the least destructive
        approach is used."

of fsck.msdos might be worth trying. You may also
call fsck.msdos directly without instructing fsck
by the option -t vfat to call it. So a possible
approach would be

fsck.msdos -w -t /dev/scramdisk/vol01

or

fsck.msdos -w -t -a /dev/scramdisk/vol01.

I hope this helps, but there is no guaranty that
the file system will be repaired successfully.


> Unfortunately, after doing this in Terminal, I still can't mount the
> container. when I click on the Volume 01 (none (don't mount))
> container and click Mount, I get the error: "Container file already
> mounted." And it gives the file system location of my container file.
> But of course it is NOT mounted there. And it is not mounted in the
> folder I selected as the Mount Point either.

You first have to unmount the container which was
mounted with the special option "none (don't mount)".

Perhaps you are confused by the two meanings of the phrase
"mount" in the context of SD4L. The first meaning is
to read the header of the container and decrypt it with
the passphrase. The second meaning is to mount the file
system within the container to make it accessible by your
Linux machine. The option "none (don't mount)" results
in only doing a "mount" in the first meaning. If this
option isn't chosen, both meanings of "mount" are performed.
So either you unmount the container before doing the normal
mount or you may perform the second meaning of "mount"
in your root terminal by the command

mount -t vfat /dev/scramdisk/vol01 /mnt

where /mnt may also be any other directory where you like
to have your container mounted.

Another possibility of mounting is to replace vfat with
msdos. The difference is that with the option -t msdos
of the mount command no long file names are available
but only 8.3 dos file names. SD4L has this option msdos
also as a separate mount option. If mounting with -t vfat
fails after all fsck runs this option -t msdos may be a
last trial.

Best regards,
Ulrich

Re: [SD4L-user] Follow-up: SD4L problem -- Windows container won't mount

[Martinveg <mar...@gm...>]

Hi Ulrich,

On Tue, Mar 17, 2009 at 4:28 AM, Hans-Ulrich Juettner
<han...@t-...> wrote:
> Hi Martin,
>
> Martinveg wrote:
>> Hi, Hans-Ulrich,
>>
>> This is a follow-up to my previous message of yesterday:
>>
>> Today I tried again to mount the container, and when it wouldn't
>> mount, I followed your instructions again, doing the fsck -t vfat
>> /dev/scramdisk/vol01 command. And the result appeared to be exactly
>> the same as yesterday. This suggests to me that the command did not
>> change my container file at all -- indeed, the notation: "Leaving file
>> system unchanged" suggests this. I commanded it to correct the
>> problems and delete the bad files, but it seems that it didn't do it.
>>
>> How do I get it to actually make the required changes?
>>
>> Thanks again,
>>
>> Martin
>>
>
> Yes that means, that the changes haven't been written.

Okay, but why weren't they written? I should point out that I'm a
newbie to Linux. I just installed Mint two weeks ago and have a lot to
learn. When the fsck -t vfat /dev/scramdisk/vol01 command was
executing, the Terminal asked me several times what to do, for
example, correct a problem or leave it alone. It would give me a
choice of 1 or 2, and I would key 1 or 2 and then press enter.

I don't even know if that is the correct thing to do in Terminal. Did
I do that correctly?

Can that command be changed so that it will actually fix the file and
save the changes?

> There are a number of further options you may try.
> By the command
>
> man fsck.msdos
>
> a manual page of the msdos/vfat file system checker,
> which fsck calls with the option -t vfat, is displayed.
> You can always find such man pages in the internet
> if they are not installed on your computer or you
> like a more friendly presentation in the browser.
> Especially the options (copied from the man page)
>
> -w for "Write changes to disk immediately."
> -t for "Mark unreadable clusters as bad."
> and perhaps
> -a for "Automatically repair the file system.
>        No  user  intervention  is necessary.
>        Whenever  there  is more than one method
>        to solve a problem, the least destructive
>        approach is used."

Thanks. But, again, I'm a novice to Linux. Can you give me a complete
command to use man fsck.msdos to automatically fix the container
mounted on
scramdisk Vol01?

Since you mentioned man fsck.msdos first, i assume i should try it
before the one that follows:

>
> of fsck.msdos might be worth trying. You may also
> call fsck.msdos directly without instructing fsck
> by the option -t vfat to call it. So a possible
> approach would be
>
> fsck.msdos -w -t /dev/scramdisk/vol01
>
> or
>
> fsck.msdos -w -t -a /dev/scramdisk/vol01.
>
> I hope this helps, but there is no guaranty that
> the file system will be repaired successfully.
>
>
>> Unfortunately, after doing this in Terminal, I still can't mount the
>> container. when I click on the Volume 01 (none (don't mount))
>> container and click Mount, I get the error: "Container file already
>> mounted." And it gives the file system location of my container file.
>> But of course it is NOT mounted there. And it is not mounted in the
>> folder I selected as the Mount Point either.
>
> You first have to unmount the container which was
> mounted with the special option "none (don't mount)".
>
> Perhaps you are confused by the two meanings of the phrase
> "mount" in the context of SD4L. The first meaning is
> to read the header of the container and decrypt it with
> the passphrase. The second meaning is to mount the file
> system within the container to make it accessible by your
> Linux machine. The option "none (don't mount)" results
> in only doing a "mount" in the first meaning. If this
> option isn't chosen, both meanings of "mount" are performed.
> So either you unmount the container before doing the normal
> mount or you may perform the second meaning of "mount"
> in your root terminal by the command
>
> mount -t vfat /dev/scramdisk/vol01 /mnt
>
> where /mnt may also be any other directory where you like
> to have your container mounted.


Is this the same thing as doing it with the GUI? I prefer to use the GUI.


> Another possibility of mounting is to replace vfat with
> msdos. The difference is that with the option -t msdos
> of the mount command no long file names are available
> but only 8.3 dos file names. SD4L has this option msdos
> also as a separate mount option. If mounting with -t vfat
> fails after all fsck runs this option -t msdos may be a
> last trial.

Okay, thanks Ulrich. I guess I'd like to know, first, if I can modify
your original command, fsck -t vfat /dev/scramdisk/vol01 , to make it
really fix the container. Then, I'd like to know an actual command to
run for man fsck.msdos. And then, I can try the fsck.msdos -w -t -a
/dev/scramdisk/vol01. And if all that fails, I will try to mount it as
MS-DOS.

Thanks so much for all your assistance.

Martin