Jigdo
Encyclopedia
Jigdo is a download utility initially designed around the Debian
distribution of GNU
/Linux
that downloads files from several mirrors in order to build an optical disk image
. Jigdo is free software
, released under the GNU General Public License
. Currently Ubuntu
, Fedora
, Solaris, and FreeBSD
, are also available through Jigdo.
A typical application of Jigdo is with its
Jigdo was implemented in Debian in order to reduce the need to have many CD image mirror sites
, locations with sufficient disk space and bandwidth to serve numerous 650 MB files (and in more recent times, 4.7 GB files for DVD
images and 25 GB files for BD images). Instead, Jigdo files allow mirrors to carry the regular Debian archive, where packages are not grouped together in image files and instead kept separately where they are also accessible through apt-get and still allow for the making of optical disk images.
A second benefit is that if files on the CD image change, Jigdo only downloads the changed files and assembles a new CD image. In this way upgrading of CD images requires much less downloading.
9 Alpha, all future release of Fedora will provide Jigdo as an alternative download method for people without BitTorrent access. Also, Jigdo versions of Fedora 8 discs are available as well as many other variants.
Debian
Debian is a computer operating system composed of software packages released as free and open source software primarily under the GNU General Public License along with other free software licenses. Debian GNU/Linux, which includes the GNU OS tools and Linux kernel, is a popular and influential...
distribution of GNU
GNU
GNU is a Unix-like computer operating system developed by the GNU project, ultimately aiming to be a "complete Unix-compatible software system"...
/Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
that downloads files from several mirrors in order to build an optical disk image
Disk image
A disk image is a single file or storage device containing the complete contents and structure representing a data storage medium or device, such as a hard drive, tape drive, floppy disk, CD/DVD/BD, or USB flash drive, although an image of an optical disc may be referred to as an optical disc image...
. Jigdo is free software
Free software
Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...
, released under the GNU General Public License
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. Currently Ubuntu
Ubuntu (operating system)
Ubuntu is a computer operating system based on the Debian Linux distribution and distributed as free and open source software. It is named after the Southern African philosophy of Ubuntu...
, Fedora
Fedora (operating system)
Fedora is a RPM-based, general purpose collection of software, including an operating system based on the Linux kernel, developed by the community-supported Fedora Project and sponsored by Red Hat...
, Solaris, and FreeBSD
FreeBSD
FreeBSD is a free Unix-like operating system descended from AT&T UNIX via BSD UNIX. Although for legal reasons FreeBSD cannot be called “UNIX”, as the direct descendant of BSD UNIX , FreeBSD’s internals and system APIs are UNIX-compliant...
, are also available through Jigdo.
A typical application of Jigdo is with its
jigdo-file utility. A user that wishes to assemble a disk image downloads a relatively small file called imagename.jigdo. The jigdo-file utility invoked with this file as an argument then proceeds to fetch additional files from the Internet: imagename.template and a series of .deb files that are listed in the .jigdo file. It then uses the mkisofs utility to build the ISO image.Jigdo was implemented in Debian in order to reduce the need to have many CD image mirror sites
Mirror (computing)
In computing, a mirror is an exact copy of a data set. On the Internet, a mirror site is an exact copy of another Internet site.Mirror sites are most commonly used to provide multiple sources of the same information, and are of particular value as a way of providing reliable access to large downloads...
, locations with sufficient disk space and bandwidth to serve numerous 650 MB files (and in more recent times, 4.7 GB files for DVD
DVD
A DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than Compact Discs while having the same dimensions....
images and 25 GB files for BD images). Instead, Jigdo files allow mirrors to carry the regular Debian archive, where packages are not grouped together in image files and instead kept separately where they are also accessible through apt-get and still allow for the making of optical disk images.
A second benefit is that if files on the CD image change, Jigdo only downloads the changed files and assembles a new CD image. In this way upgrading of CD images requires much less downloading.
Fedora
Since the release of FedoraFedora (operating system)
Fedora is a RPM-based, general purpose collection of software, including an operating system based on the Linux kernel, developed by the community-supported Fedora Project and sponsored by Red Hat...
9 Alpha, all future release of Fedora will provide Jigdo as an alternative download method for people without BitTorrent access. Also, Jigdo versions of Fedora 8 discs are available as well as many other variants.