sha1sum output: what does it mean?

[Paul Howarth]

Leopoldo Olmos wrote:
> I've got the following output after running sha1sum on my recently
> downloaded (BitTorrent) FC4-x86_64-DVD.iso:
> 
> FC4-x86_64-DVD.iso: OK
> sha1sum: FC4-x86_64-SRPMS-disc1.iso: No such file or directory
> FC4-x86_64-SRPMS-disc1.iso: FAILED open or read
> sha1sum: FC4-x86_64-SRPMS-disc2.iso: No such file or directory
> FC4-x86_64-SRPMS-disc2.iso: FAILED open or read
> sha1sum: FC4-x86_64-SRPMS-disc3.iso: No such file or directory
> FC4-x86_64-SRPMS-disc3.iso: FAILED open or read
> sha1sum: FC4-x86_64-SRPMS-disc4.iso: No such file or directory
> FC4-x86_64-SRPMS-disc4.iso: FAILED open or read
> sha1sum: FC4-x86_64-disc1.iso: No such file or directory
> FC4-x86_64-disc1.iso: FAILED open or read
> sha1sum: FC4-x86_64-disc2.iso: No such file or directory
> FC4-x86_64-disc2.iso: FAILED open or read
> sha1sum: FC4-x86_64-disc3.iso: No such file or directory
> FC4-x86_64-disc3.iso: FAILED open or read
> sha1sum: FC4-x86_64-disc4.iso: No such file or directory
> FC4-x86_64-disc4.iso: FAILED open or read
> sha1sum: FC4-x86_64-disc5.iso: No such file or directory
> FC4-x86_64-disc5.iso: FAILED open or read
> sha1sum: FC4-x86_64-rescuecd.iso: No such file or directory
> FC4-x86_64-rescuecd.iso: FAILED open or read
> sha1sum: WARNING: 10 of 11 listed files could not be read
> 
> What does it mean? 
> Should I download the file again because of the missing files?

The SHA1SUM file contains checksums for all of the CD and DVD (binary 
and source) ISO images for your architecture. You only need the binary 
DVD or CD images for installation, so it's normal to see "No such file 
or directory" for all the images you didn't (need to) download. The 
checksum for the DVD ISO is OK, so you should be OK to install from it.

Paul.