Hi guys I got a distro that I want to copy for a friend but the second CD is a bit scratched and I would not want to give him a corrupted CD ( even if it is only some files). So I wana checksum it the same way I didwhen I downloaded the CDs .

The question is can I checksum it the way it is ( I dont thnik this is possible since there are multiple files rather than one single file in iso format). But I guess nothin is wrong with askin

Or do I have to create an iso image first and then checksum it ....... to see if the CD is still absolutely valid.

Thanks... and I hope nobody minds the dumb question

You should create an iso, but even than a checksum will not tell you if the iso integrity is ok. Only in comparison to another original iso.

I mean I downloaded the original iso from iso.linuxquestions.org....
and the checksum is noted there......so if I compare it with that checksum everything will be allright ??

Yes you can do it this way...no need to do anything other than downloading the iso and haveing the checksum and running the check command(think thats what the command is called).

You can generate the md5 checksum of the CD with

thaks netz that was what I was aiming for

Can anyone suggest how to perform checksum test between two CD's

md5sum /dev/hdb /dev/hdc
(replace hdb and hdc with where the two cdrom drives are, watch out or you could try to compare your hard drive to it).

See if the output is the same on both lines. If its different, or if you get an input/output error, somethings wrong.

I'm working with this using

md5sum /dev/cdrom /dev/cdrom1

Thank you