Differences between revisions 96 and 97
Revision 96 as of 2010-09-30 20:04:29
Size: 4737
Comment:
Revision 97 as of 2012-02-09 15:45:53
Size: 6269
Editor: ?SamuliSeppänen
Comment: Added information about preseeding options
Deletions are marked like this. Additions are marked like this.
Line 5: Line 5:
= Preseeding methods =

As mentioned in the [[http://www.debian.org/releases/etch/i386/apbs01.htmlfrom .en|official installation guide]], there are several ways to feed the preseed file to the installer.

== Adding the preseed file to the installer's initrd.gz ==

Installation can be fully automated by adding a preseed file to the installer ISO's initrd.gz. This method is described in detail in [[DebianInstaller/Preseed/EditIso|this wiki article]]. The downside of this method is that net installer has to be generated whenever a preseed file is modified.

== Loading the preseeding file from a webserver ==

It is fairly simple to load the preseed file from a webserver. If you're installing Squeeze (or newer) and have a DHCP server on your network, this method allows almost fully automated installations; all you need to do is launch the installer with proper options:

 * When the graphical installer menu appears, press ESC
 * (Type "help" if you want view generic help)
 * Type "auto url=http://webserver/path/preseed.cfg", replacing the URL with the address to your preseed configuration file

The "auto" command launches the installation in the automated mode, where the configuration of hostname, locale and keymap are postponed so that they can be answered from the preseed file loaded from the network. You could use "install url=..." but you'd have to answer these questions manually, regardless of what you have in the preseed config.
Line 8: Line 26:
Most of the questions asked by DebianInstaller can be preseeded by setting the answers in the [[debconf]] database. The Installation Guide includes an [[http://d-i.alioth.debian.org/manual/en.i386/apb.html|extensive appendix]] dedicated to preseeding and includes a complete example. Feel free to add any information that is not covered in the manual to the notes below. Most of the questions asked by DebianInstaller can be preseeded by setting the answers in the [[debconf]] database. The Installation Guide includes an [[http://d-i.alioth.debian.org/manual/en.i386/apb.html|extensive appendix]] dedicated to preseeding and includes [[http://www.debian.org/releases/etch/i386/apbs04.html.en|a complete example]]. Feel free to add any information that is not covered in the manual to the notes below.

Translation(s): English, Français


Preseeding methods

As mentioned in the official installation guide, there are several ways to feed the preseed file to the installer.

Adding the preseed file to the installer's initrd.gz

Installation can be fully automated by adding a preseed file to the installer ISO's initrd.gz. This method is described in detail in this wiki article. The downside of this method is that net installer has to be generated whenever a preseed file is modified.

Loading the preseeding file from a webserver

It is fairly simple to load the preseed file from a webserver. If you're installing Squeeze (or newer) and have a DHCP server on your network, this method allows almost fully automated installations; all you need to do is launch the installer with proper options:

  • When the graphical installer menu appears, press ESC
  • (Type "help" if you want view generic help)
  • Type "auto url=http://webserver/path/preseed.cfg", replacing the URL with the address to your preseed configuration file

The "auto" command launches the installation in the automated mode, where the configuration of hostname, locale and keymap are postponed so that they can be answered from the preseed file loaded from the network. You could use "install url=..." but you'd have to answer these questions manually, regardless of what you have in the preseed config.

Preseeding d-i

Preseeding provides a way to set answers to questions asked during the installation process, without having to manually enter the answers while the installation is running. This makes it possible to fully automate most types of installation and even offers some features not available during normal installations.

Most of the questions asked by DebianInstaller can be preseeded by setting the answers in the debconf database. The Installation Guide includes an extensive appendix dedicated to preseeding and includes a complete example. Feel free to add any information that is not covered in the manual to the notes below.

Examples

Post here any links you have to example preseed files. Note that using any of these files directly is not wise, as a malicious person could probably come up with values for a preseed file that makes d-i misbehave. Also, the files are downloaded over http, so are vulnerable to man-in-the-middle spoof attacks. The best way to use any preseed file is to copy it to your own local web server or media, and look it over before using it.

Notes

  • Do not work off a debconf-get-selections (--installer) generated preseed.cfg but get the values from it and modify the example preseed file with them.

  • Be aware there is only one space in preseed files between subkey and value on "owner key/subkey value" lines.

  • Do not reboot in the base-config/late_command command, the installation process will start again at the start of the 2nd stage.

  • Preseeding has changed significantly in etch, preseed files for sarge will need to be updated or re-done. The largest change is the removal of base-config, which means that base-config/late_command and base-config/early_command are no longer available.

  • To install additional packages in etch, you can preseed preseed/early_command to run "apt-install package".

  • Look in debconf-devel(7) in the debconf-doc package for more docs about d-i and debian-installer preseed questions.
  • If your preseed value is being ignored and whilst using DEBCONF_DEBUG=5 to watch the debconf output you see "FSET blah false" it just means that a piece of code really wants that question to be seen, and such questions are not normally preseedable - the only way to avoid them is to avoid the situation that gives rise to that question being asked.