Many thanks to all that provided their help. Mostly I found easy to use
Thomas' suggestion:
"Thomas Hoppeer" <thoppeer@gmail.com> writes:
> To verify data on your dvd you can also use star and readcd:
> http://www.linuxconfig.org/Create_and_burn_ISO_images_with_mkisofs_%26_cdrecord#Verify_data
. Now, `readcd' would produce I/O error messages with *all* DVDs, also the ones
that I know for sure are all right. So, it was actually not useful at all.
Instead, `star' seems to do the proper job: with Sarge I did:
# apt-get install star
, then mounted the disk, then cd into it and:
$ star -cPM . >/dev/null
. With the damaged disk, it produced an output like:
star: Input/output error. Error reading 'rodolfo-30.giu.2007/mobile/opensync/libsyncml/tests/.svn/README.txt'.
, then ended up with:
star: 118167 blocks + 5120 bytes (total of 1210035200 bytes = 1181675.00k).
star: The following problems occurred during archive processing:
star: Cannot: stat 0, open 0, read/write 662. Size changed 0.
star: Missing links 0, Name too long 0, File too big 0, Not dumped 0.
star: Processed all possible files, despite earlier errors.
. Instead, with the brand new DVD the output was:
star: 119837 blocks + 9216 bytes (total of 1227140096 bytes = 1198379.00k).
. So it seems that I can use this tool to verify disk integrity. I didn't try
other people suggestions because this one was the simplest for me. Only one
thing: the command `apt-get install star' does not work with Etch: it knows no
package named `star'. Any suggestion about how to install star under Etch?
Thanks indeed,
Rodolfo