To check the md5sum from a just burned dvd:
$ md5sum /dev/dvd
Trailing zero’s and nuls at the end can change the MD5 hash. So to calculate the md5sum we need to:
1) find the size of the ISO in bytes
2) run dd with this exact size in bytes: dd if=/dev/dvd | head –bytes= | md5sum
So for example:
$ dd if=/dev/dvd | head –bytes=3621957632 | md5sum