opsi manual opsi version 4.0.2 - opsi Download - uib

opsi manual opsi version 4.0.2
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It also holds the information on how to partition the hard disk, what file system to use and which operating system
to install. Also it provides the encrypted password to connect the file share.
These information will be combined with some information taken from the dhcp response and then be passed to the
installation script for further processing.
Then the password for the user pcpatch will be decrypted with the transferred key to mount the installation share
and then call the installation script from the mounted share to start the installation of the operating system. What
specific operations the script performs depends on the operating system which is to be installed. Below the steps of a
Windows XP installation will be described.
Prepare the disc: On the hard disk the bootimage creates a new partition (of size 6 GB), formats it and installs a
bootable ntloader kernel.
Copy the installation file: The files required for OS installation and the setup files for the opsiclient-agent
(which is the opsi software distribution pack) will be copied from the server file share (e.g.
/opt/pcbin/install/winxppro/i386) to the local hard disk.
Maintain the configuration informations: Some of the configuration and control files contain replacement characters,
which will be patched before starting the actual installation. With a specified script (patcha-script) the
placeholders will be replaced with parameters taken from the information packet, which is built from configuration
files and the dhcp-response. For example the file unattend.txt, which is the control file for unattended OS Installation,
will be patched with specific information like host IP, client IP, client name, workgroup, default gateway etc..
Prepare Reboot: Bootrecords will be installed which will start the Windows setup program at the next reboot. The
patched unattend.txt is passed to the setup as the control file for unattended installation.
Reboot: During the previous boot, the named pipe (which is indicating a request for installation) has been removed
by reading it once. So the next PXE boot will load the default netboot response, which executes the command hdboot.
The local boot loader will be started and the setup for operating system installation starts.
These steps are controlled by an OS specific python script.
9.2.7 Installation of OS and opsi-client-agent
The OS installation is based on the Microsoft unattended setup. Part of this is the standard hardware detection. In
addition to the possibilities given during an installation from non-OEM or slipstreamed installation media, drivers and
patches (i.e. service packs) can be installed during the initial installation, making the separate installation of drivers
obsolete.
One feature of the unattended installation is the possibility to initiate additional installations after the main installation
is finished. This mechanism is used to install the opsi-client-agent, which implements the automatized software
distribution system. An entry in the registry marks the machine as being still in the reinstallation-mode.
The final reboot leads to starting the opsi-client-agent service for software distribution prior to the first user login.
Based on the value of the aforementioned registry key the opsi-client-agent switches into reinstallation-mode. Therefore,
regarding the configuration status of each software packet, each packet which is marked as action status ”setup”
or installation status ”installed” within the configuration of that client will be installed. After all the designated
client software has been installed, the reinstallation process is finished and the internal status is switched back from
reinstallation-mode to standard-mode. In standard-mode only software packages that are marked as action status
”setup” will be installed.
9.2.8 How the patcha program works
As mentioned above the information collected from dhcp and opsi-webservice will be used to patch some configuration
files as e.g. unattend.txt. The program used for patching is the script /user/local/bin/patcha.
This script replaces patterns like @flagname() in a file with values taken as flagname=value from a control file (default
input is /proc/cmdline). In the files that have to be patched, the search and replace pattern must start with @, might
have an optional after the flagname and must have one or more trailing .
So by calling patcha the file will be patched with information taken from /proc/cmdline.