Installation images are used to speed installation up. Each separate image contains a compact part of a filesystem. Several images can be combined together to finally create several different complete systems - the only unique image for each such system is a separate image containing RPM (plus other metadata) database for a particular system.
Example of images on media:
Available Images: * Base_System * Xorg * Additional_Tools * Metadata_image_*, one for each imageset
Example of imagesets (combinations of images):
Base System: + Base_System + Metadata_image_1 (Base_System.meta) Advanced System: + Base_System + Xorg + Metadata_image_2 (Base_System.meta + Xorg.meta) Superadvanced System + Base_System + Xorg + Additional_Tools + Metadata_image_3 (Base_System.meta + Xorg.meta + Additional_Tools.meta)
*.lzma (((files)tar)lzma) - TAR* archive additionally compressed with LZMA
*.xz - (((files)tar)lzma) - TAR* archive additionally compressed with newer LZMA
*.tar.bzip2, *.tar.gz (((files)tar)bzip2/gzip) - TAR*/Bzip2; resp. TAR*/Gzip archive
* Each TAR archive is created with: --numeric-owner --checkpoint=400 --record-size=10240
If we want to use installation images, we have to describe them first. See the example of /images/images.xml file stored on the first installation media:
<xi:include></xi:include>This XML file describes sets of images from which an installation chooses the best-matching one according to <patterns>...</patterns> item defined in each imageset.
Each imageset contains one or more images. To provide a useful feedback when deploying the images, they have to be described in /images/details-${ARCH}.xml, respectively in file /images/details.xml stored on the first installation media:
<xi:include></xi:include>${ARCH} is one of: i386, sparc, mips, ppc, alpha, s390, ia64, and x86_64.
Mandatary items for each image (file name) are file and size (in bytes).