checking live usb before using it

[ternor]

Hello.  I apologise if this has been discussed.  I can find no silver amongst the dross.

I have created my first live usb from the latest LXDE iso.  The iso md5sum is correct.

I know how to get the md5sum of a live disk but cannot work out or find any procedure to get the md5sum of a live usb.

As a second best option I tried "mediacheck /dev/sdb."  I get the message "Unable to find install image /dev/sdb" even when running the command while in the directory containing the iso.

The command "mediacheck --help" produced the same message.  There is no man page for 'mediacheck'.  I read parts of a long thread on mediacheck and livecd and early posts mentioned that mediacheck is defective.

Is there any way to check a live usb before using it?  If so, how?

EDIT: It has just occurred to me that I could try creating an iso from the usb and comparing the md5sum of the second iso.

[Just17]

I would suggest you check the md5sum of the   .sqfs file on the USB, and do the same for the .sqfs file you can extract from the ISO.

[ternor]

OK.  Thanks.

[djohnston]

According to the Synaptic description:

The mediacheck package contains utilities for the insertion and verification of embedded MD5 checksums in iso images.

[ternor]

Thanks.  Does that mean you can't use it to check disks?  It is of no use for isos when md5sum and other check sums are available.

[djohnston]

Does that mean you can't use it to check disks?

Yes. There was a lengthy discussion about it here.

[ternor]

Thanks.