1. Go to the directory where is your ISO file assuming you have downloaded
http://cdimage.debian.org/debian-cd/...i386-DVD-1.iso
2. type sha512sum debian-7.1.0-i386-DVD-1.iso
3. then check the output against the file
http://cdimage.debian.org/debian-cd/...dvd/SHA512SUMS
4. so is should look like this:
a01ab43f552c1c444e9be3f2f61e5b9a28e7a8c70764a188161870b31279b8532b768b4f245c9992f1d76a3c72ee2c512d4e 2531ef7db5a5a0f3ef8b8bf080d0 debian-7.1.0-i386-DVD-1.iso
I have never used Jigdo as mention in the post so tried it now just to check how it works and I am surprised how quick it was, here is what I did:
1. to install jigdo: sudo apt-get install jigdo-file
2. run the program in directory you want the Image (ISO) saved to: jigdo-lite
3. it needs 2 files:
http://cdimage.debian.org/debian-cd/...386-CD-1.jigdo
http://cdimage.debian.org/debian-cd/...-CD-1.template
4. then I have pressed 1 for 1 CD
5. enter for the mirror to be UK
and her is what it looked like at the end:
2013-08-25 15:34:33 (1.37 MB/s) - `debian-7.1.0-i386-CD-1.iso.tmpdir/ftp.uk.debian.org/debian/pool/main/e/expat/libexpat1_2.1.0-1_i386.deb' saved [140366/140366]
FINISHED --2013-08-25 15:34:33--
Total wall clock time: 3.3s
Downloaded: 10 files, 5.4M in 3.1s (1.73 MB/s)
Found 10 of the 10 files required by the template
Successfully created `debian-7.1.0-i386-CD-1.iso'
-----------------------------------------------------------------
Finished!
The fact that you got this far is a strong indication that `debian-7.1.0-i386-CD-1.iso'
was generated correctly. I will perform an additional, final check,
which you can interrupt safely with Ctrl-C if you do not want to wait.
OK: Checksums match, image is good!
So I have checked the sha512sum as well, to see if it worked and here is the output:
sha512sum debian-7.1.0-i386-CD-1.iso
f83ddd502c442a5fb44a618d0cd45b109b6d7db547194674d4408b9398691e96a35993636d7d54692c46005985b66f929de0 f51a6934b136213668e55ee82473 debian-7.1.0-i386-CD-1.iso
comparing it to
http://cdimage.debian.org/debian-cd/...-cd/SHA512SUMS and it is identical, will use it next time I download ISO images.