Jigdo:Jigsaw Download

Accidently I came across Jigdo through a mailing list, a very useful tool when it comes to downloading/updating ISO images of a GNU/Linux distribution.

The usual method that I follow when I download ISO images of a distribution is start the download through either Wget (http://www.gnu.org/software/wget) or use the default browser download manager.Although both have failed on me a couple of times & that isnt the point of this post anyways(i think i seriously need to stick to torrents for downloading large files),but I keep downloading newer distributions in ISO image format whenever a new version is out.Delete the old version & keep the latest one dumped on my hard drive.Burn the ISO for myself & friends for giving it away.

Downloading the same entire distribution again for subtle changes that have occured since the last version is a PITA :).Seriously,although I'm a 256 kbps unlimited pipe from Airtel I never like it.

Here is where Jigdo comes into picture,say you have a ISO image on your hard drive or a CD mounted with the loop option & say a new version of the ISO is available then Jigdo will update the ISO image or create a new updated ISO image as in the latter case.

The procedure is simple,you need to get .jigdo & .template file for every ISO image that you want to update.For example if you want to update Debian Stable the first 3 cds then you need to get hold of .jigdo & .template files for each CD.

You need then use the package jigdo-lite which makes this process a walk in the park if you follow the steps properly.

With the below steps I installed jigdo-lite

$sudo apt-get update

swapneel@ubuntu:~$ sudo apt-cache search jigdo-lite
Password:
jigdo - GTK+ download manager
jigdo-file - Download Debian CD images from any Debian mirror

jigdo-file is the package which contains jigdo-lite.

swapneel@ubuntu:~$ sudo apt-get install jigdo-file
Reading package lists… Done
Building dependency tree… Done
jigdo-file is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 3 not upgraded.

In my case I had already installed jigdo-file sometime back to give this a try,thats why its saying already the newest version.

I have a Debian Sarge 3.1ISO image present on my laptop, debian-31r1-i386-binary-1.iso
I've mounted the ISO images as a loop device as shown below,

swapneel@ubuntu:/home/jigdo$ sudo mount -o loop debian-31r1-i386-binary-1.iso /mnt/

I got the .jigdo & .template files required for the above ISO from the below url, For me it was debian-31r2-i386-binary-1.jigdo & debian-31r2-i386-binary-1.template

http://cdimage.debian.org/debian-cd/current/i386/jigdo-cd/

The next step is to run jigdo-lite along with the .jigdo file you have downloaded for the ISO.

I'm too sleepy right now so I'll upload the image which has the remaining steps in it.

The below screenshot shows jidgo taking the latest .jigdo file & updating the mounted ISO to create a new ISO image.

The jigdo script calls for the location where the ISO is mounted as a loop device.

Files to scan : /mnt

I had also downloaded the .template file earlier,so it doesnt download & starts checking what should be updated.

Copied input files to temporary file `debian-31r2-i386-binary-1.iso.tmp ' - repeat command and supply more files to continue

The above confirms that new files were found & have been updated & saved as debian-31r2-i386-binary-1.iso.tmp .It then prompts for the next ISO image to be updated.

A new updated ISO file with a .tmp at the end of the file is saved under the directory from which you issued the jido-lite command.The below screenshot shows about the newly updated ISO

As you can see the attributes of the old & new ISO image files,

-rwxr-xr-x 1 root root 669585408 2006-04-25 02:26 debian-31r1-i386-binary-1.iso
-rw-r–r– 1 root root 667164837 2006-04-25 02:39 debian-31r2-i386-binary-1.iso.tmp

The only thing remains is to burn the new ISO image on a blank CD & you are ready go.Kickass !!

Unfortunately I have not been able to find jigdo files for other distributions like Ubuntu,Fedora Core which I would love to see.

If anyone knows about the locations of these then please reply here.

The above article is original & written by me & was inspired from here : http://atterer.net/jigdo/debian-jigdo-mini-howto/