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Revision as of 10:23, 6 July 2012 by Urilabob (talk | contribs) (→‎Updates from the Tree: : Make clear that the name must be exactly updates.img (often distributed in form updates*img))

Anaconda Updates

anaconda has the capability to incorporate updates at runtime to fix any bugs or issues with the installer. These updates are generally distributed as a disk image file (referred to as updates.img from here on out). The updates.img can be used in a few different ways.


Updates types

There are a number of sources for the updates.

Updates from the Network

The easiest and most popular way to use an update.img is via the network. This is how almost all updates images you'll see in bug reports and mailing lists are distributed. This does not require you modify your installation tree at all.

To use this method, simply boot with:

 linux updates=http://some.website.com/path/to/updates.img

If you have multiple network interfaces, anaconda will first prompt you to select one (unless you have used the ksdevice= boot parameter). It will then attempt to configure this link using DHCP. If you require other networking configuration, you will need to use various options. ksdevice= can be used to specify a different network device, and the ip= option (along with others for gateway, nameserver, and so forth) can be used for static configuration. All anaconda config options are described elsewhere .

If you are making your own updates.img, just upload it to a web server you have access to and pass the location as above.

Updates from a disk image

You can also put an updates.img on a block device (either a floppy or a USB key). This can be done only with an ext2 filesystem type of updates.img. For a floppy drive, insert your floppy and then run

 dd if=updates.img of=/dev/fd0 bs=72k count=20

to put the contents of the image on your floppy. Then, boot the installer with

 linux updates

and you will be prompted to provide the location of your update disk.

You can also use a USB key or flash media -- just replace /dev/fd0 with the device that your USB key is at.

Updates from the Tree

If you're doing a CD, hard drive, HTTP, or FTP install you can also put the updates.img in your tree to be picked up by all installs automatically. Put the file in the images/ directory. It must have exactly the name updates.img, even if you received it with a different name.

For NFS installs, there are two options. You can either put the image in images/ as above or explode the image into the RHupdates/ directory in your installation tree.

How to Create an Anaconda Updates Image

If you are working on anaconda or looking at a bug and want to test your own bug fixes, it's easy to create your own updates.img file. anaconda supports two formats: an ext2 filesystem image and the more common gzip-compressed cpio archive. The automatic tools shipped with anaconda deal in the second form, so that's what will be discussed here.

The easiest way to create an image is to run

   ./configure
   make updates

from the anaconda source tree. This will package up all the changes to the tree since the last release and create a file named "updates.img" in the top of the tree. Remember to use the correct git branch for the Fedora release you are working on or testing. If you need finer control over this process (like creating an image from an even older release), or you don't want to run ./configure first (the make command will fail unless ./configure has been run), run

   scripts/makeupdates

by hand. The help screen documents the several options that can be used.

An updates.img can include more than just files from anaconda, though. It can also include shared libraries, graphics, other python modules, and certain data files used by anaconda. To add files to an existing image (or create an entirely new one), just do the following:

   scripts/upd-updates updates.img file1 file2 ...

Note that the placement of files in an image is a little picky. For instance, python modules must be in their proper subdirectory mirroring the layout of /usr/lib/python?.?/site-packages/.

How to Examine an Anaconda Updates Image

updates.img files provided by the Fedora project and generated by the makeupdates script are compressed cpio archives. To examine one of these files, use /sbin/lsinitrd.

To explode one, do the following:

$ mkdir dest
$ cd dest
$ gunzip -dc /path/to/updates.img | cpio -id