Copying USB stick fails with device errors

[Alex]

Hi,

>> I've also tried creating the backup using just "cat /dev/sdb1>
>> usbstick.dd" and it's the same result. I believe I mentioned in my
>> previous post that there does appear to be a filesystem and partition
>> table there?
>>
>> # fdisk -l usbstick.dd
>>
>> Disk usbstick.dd: 1342 MB, 1342169088 bytes
>> 45 heads, 4 sectors/track, 14563 cylinders, total 2621424 sectors
>> Units = sectors of 1 * 512 = 512 bytes
>> Sector size (logical/physical): 512 bytes / 512 bytes
>> I/O size (minimum/optimal): 512 bytes / 512 bytes
>> Disk identifier: 0x261e6d11
>>
>>       Device Boot      Start         End      Blocks   Id  System
>> usbstick.dd1   *           4     5242859     2621428    b  W95 FAT32
>>
>> Thanks,
>> Alex
>
> I might be wrong,  but....
> the usb stick drive may have firmware that
> presents 2 devices to the host. It is similar to
> connecting a usb hub to your computer, and then
> inserting 2 ordinary usb drives into the hub, which
> then appear on the host as sdb and sdc.
> I do not know of a linux tool that will let you
> dd both of these devices as a single device image.
> Perhaps someone on this list might know of such
> a util.

I'm more interested in figuring out how to mount this block device on
a loopback.

I believe the problem is that the filesystem starts at block 4 and not
at the beginning, so mount can't figure out how to mount it.

Thanks,
Alex