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cccc	04-28-2010 03:47 AM

compare the contents of two DVDs

hi

Howto compare the contents of two DVDs, for example using the MD5-fingerprint, if all data was exact copied and no burning errors?

zordrak

04-28-2010 04:23 AM

Quote:

$ md5sum /dev/sr0

Or, whatever your DVD device node is e.g. /dev/dvd.

cccc	04-28-2010 09:30 AM

Quote:

Originally Posted by zordrak (Post 3950318)

Or, whatever your DVD device node is e.g. /dev/dvd.

thx, but on my debian squeeze I'm getting the following:

Code:

# md5sum /media/cdrom

md5sum: /media/cdrom: Is a directory

zordrak

04-28-2010 09:36 AM

That's not the device node, that's the mount point.

Type:

Code:

$ mount

And look at what device is mounted on /media/cdrom

cccc	04-28-2010 06:56 PM

sorry, but using:

Code:

 

# md5sum /dev/sr0

md5sum: /dev/sr0: Input/output error

pixellany

04-28-2010 07:19 PM

Did you use the "mount" command to confirm what the node is?

I just tried this here and it seems to work. I cannot, however, duplicate your error message by entering some random node name.

You might try running the command as root......

cccc	04-28-2010 07:35 PM

Quote:

Originally Posted by pixellany (Post 3951217)

Code:

# mount

/dev/sda3 on / type ext3 (rw,errors=remount-ro)

tmpfs on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)

proc on /proc type proc (rw,noexec,nosuid,nodev)

sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)

udev on /dev type tmpfs (rw,mode=0755)

tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)

devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=620)

fusectl on /sys/fs/fuse/connections type fusectl (rw)

/dev/sda8 on /home type ext3 (rw)

/dev/sda7 on /tmp type ext3 (rw)

/dev/sda6 on /var type ext3 (rw)

/dev/sda2 on /windows type fuseblk (ro,allow_other,blksize=4096)

/dev/sr0 on /media/cdrom0 type udf (ro,noexec,nosuid,nodev)

and I'm doing this command on squeeze as root.

pixellany

04-28-2010 09:39 PM

So far, it all makes sense, but...

Can you read the contents of the DVD using the file manager? If not, is it possible that it is just a bad disk? (I'm grabbing at straws here, but I assume that it's possible get a bad burn in such a way that md5sum could not read the disk.)

How about the other disk?

cccc	04-29-2010 04:45 AM

Quote:

Originally Posted by pixellany (Post 3951300)

I can read the contents of the DVD using the file manager without any problems and this DVD disc is not bad.
On others DVDs md5sum works without any problems.
Any other idea what's wrong?

zordrak

04-29-2010 05:36 AM

Difficult to say, Input/Output error usually means that there really is something wrong.

Try taking an image of the disc and then doing an md5sum on that:

Code:

$ dd if=/dev/sr0 of=~/disc-image.img

$ md5sum ~/disc-image.img

cccc	05-02-2010 11:44 AM

Quote:

Originally Posted by zordrak (Post 3951632)

Difficult to say, Input/Output error usually means that there really is something wrong.

Try taking an image of the disc and then doing an md5sum on that:

Code:

$ dd if=/dev/sr0 of=~/disc-image.img

$ md5sum ~/disc-image.img

Thx, it seems to work.

cccc	05-02-2010 11:45 AM

BTW Howto to display file differences between 2 DVDs?

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