8.9. S/390, zSeries: The Boot Loader ZIPL

Once the system is installed on your DASD, you need to write initial information for the IPL from disk, such as the location of the kernel image and a parameter line. This is done by means of the tool ZIPL, which retrieves this information from the command line or a configuration file.

8.9.1. For Kernel Version 2.6.x

The syntax of ZIPL is as follows:

zipl [options] [configuration]

 Options:
 -h or --help     prints this information
 -c <CONFIG-FILE> or --config=<CONFIG-FILE>
      <CONFIG-FILE> specifies the config file to be used.
      This option overrides the environment variable
      ZIPLCONF.

The following options override settings in the configuration file. ARG indicates a required argument. [ARG] shows an optional argument.

-t <DIRECTORY> or --target=<DIRECTORY>

DIRECTORY specifies the target directory where zipl installs some files needed for the IPL process.

-i <IMAGE[,ADDRESS]> or --image=<IMAGE[,ADDRESS]>

IMAGE specifies the file name of the bootable image. [ADDRESS] specifies the address where the image will be loaded in the memory.

<RAMDISK[,ADDRESS]> or --ramdisk=<RAMDISK[,ADDRESS]>

RAMDISK specifies the file name of the RAM disk to load. [ADDRESS] specifies the address where the RAM disk will be loaded in the memory.

<PARMFILE[,ADDRESS]> or --parmfile=<PARMFILE[,ADDRESS]>

PARMFILE specifies the file name of the parm file to load. [ADDRESS] specifies the address where the parm file will be loaded in the memory.

-d <PARTITION> or --dumpto <PARTITION>

PARTITION specifies the device node of the partition on which the dump will be created. Example:/dev/dasdb1 or /devfs/dasd/0192/part1

The command ZIPL reads the configuration file in /etc/zipl.conf and uses the parameters listed in the file.

8.9.2. The ZIPL Configuration File

The configuration file for the ZIPL boot loader resides in the directory /etc/zipl.conf. Example 8.3. “/etc/zipl.conf” shows a zipl.conf file. It is divided into several sections. You can define more than one way for IPLing your Linux system.

Example 8.3. /etc/zipl.conf

[defaultboot]
default=ipl

[ipl]
target=/boot/zipl
image=/boot/zilo-kernel/image
#ramdisk=/boot/initrd
parameters="dasd=0150 root=/dev/dasda2 noinitrd"

[dumptape]
target=/boot
dumpto=/boot/zipl

The section [defaultboot] defines the section to use be called if you call ZIPL without any parameters. The line parameters= defines the commands given to the kernel during start-up. Here, specify which DASDs should be used and which one contains the root file system. To add specific DASDs in the parameter line, use something like:

parameters="dasd=0150,0151,0152 root=/dev/dasda2 noinitrd"

To add a DASD range, use a format like that used in the following:

parameters="dasd=0150-0155 root=/dev/dasda2 noinitrd"
[Important]DASDs and the Command Line

Add or delete DASDs or DASD ranges from the parameter line. However, do not remove the DASD containing the root file system. Otherwise, the system will not be able to boot.