3.2. linuxrc

Every machine has special BIOS routines that are executed on start-up to initialize the hardware. During the actual boot process, these routines load an image that is executed by the machine and controls the remaining boot process. The image normally is a boot manager that enables the user to select an installed system or an installation system. When selecting installation of SUSE LINUX, a boot image containing a kernel and a program called linuxrc is loaded.

linuxrc is a program that analyzes and initializes the system for the actual installation process. It runs without user interaction and starts YaST after finishing the hardware detection and loading modules needed for the installation process.

The use of linuxrc is not limited to the installation. You can also use it as a boot tool for an installed system and even for an independent RAM disk–based rescue system. Refer to Section 5.4, “The SUSE Rescue System” for details.

If the system uses an initial RAM disk (initrd), a shell script also called linuxrc handles the loading of modules during boot. This script is generated dynamically by the script /sbin/mkinitrd. It is completely different from and should not be confused with the program linuxrc that is used for installation.

It is possible to pass parameters that change the behavior of the start-up to linuxrc. linuxrc looks for an info file on a floppy disk or in the initrd in /info. Subsequently, linuxrc loads the parameters at the kernel prompt. You can edit the default values in the file /linuxrc.config. However, the recommended method is to implement changes in the info file.

[Tip]Tip

It is possible to run linuxrc in a manual mode. To do this, use the parameter "manual=1" at the install prompt.

An info file consists of keywords and values in the format key: value. These pairs of keys and values can also be entered at the boot prompt provided by the installation medium using the format key=value. A list of all keys is available in the file /usr/share/doc/packages/linuxrc/linuxrc.html. The following list shows some of the most important keys with example values:

Install: URL (nfs, ftp, hd, etc.)

Specifies the installation source as a URL. Possible protocols include cd, hd, nfs, smb, ftp, http, and tftp. The URL syntax corresponds to the common form used in Web browsers, for example:

  • nfs://<server>/<directory>

  • ftp://[user[:password]@]<server>/<directory>

Netdevice: <eth0>

The Netdevice: keyword specifies the interface linuxrc should use, if there are several ethernet interfaces available.

HostIP: <10.10.0.2>

Specifies the IP address of the host.

Gateway: <10.10.0.128>

This specifies the gateway through which the installation server can be reached, if it is not located in the subnetwork of the host.

Proxy: <10.10.0.1>

The Proxy: keyword defines a proxy for the FTP and HTTP protocols.

ProxyPort: <3128>

This specifies the port used by the proxy, if it does not use the default port.

Textmode: <0|1>

This keyword enables starting YaST in text mode.

VNC: <0|1>

The VNC parameter controls the installation process via VNC, which makes the installation more convenient for hosts that do not have a graphical console. If enabled, the corresponding service is activated. Also see the VNCPassword keyword.

VNCPassword: <password>

This sets a password for a VNC installation to control access to the session.

UseSSH: <0|1>

This keyword enables access to linuxrc via SSH when performing the installation with YaST in text mode.

SSHPassword: <password>

This sets the password for the user root to access linuxrc.

Insmod: <module parameters>

This specifies a module the kernel should load and any parameters needed for it. Module parameters must be separated by spaces.

AddSwap: <0|3|/dev/hda5>

If set to 0, the system does not try to activate a swap partition. If set to a positive number, the partition corresponding to the number is activated as a swap partition. Alternatively, specify the full device name of a partition.


SUSE LINUX Administration Guide 9.3