Parameter overview

Red Hat Enterprise Linux 8.6 LPAR mode z/VM guest KVM guest

You might need to know all zipl options and how to specify them on the command line, in the zipl configuration-file, or in a BLS snippet.

Option
Explanation
Command line:
-a
--add-files
Causes kernel image, kernel parameter file, and initial RAM disk to be added to the bootmap file in the target directory rather than being referenced from this file.

Use this option when these files are spread across multiple disks to ensure that they are available at IPL time. Specifying this option significantly increases the size of the bootmap file that is created in the target directory.

Command line:
-b <bls_dir>
--blsdir=<bls_dir>
Specifies the directory where zipl finds files with BLS snippets. You can change the default directory, /boot/loader/entries, with the BOOT environment variable.

See BLS configuration snippets.

Command line:
-c <config_file>
--config=<config_file>
Specifies the configuration file. You can change the default configuration file /etc/zipl.conf with the environment variable ZIPLCONF.
Command line:
<configuration>
Specifies a configuration section in a zipl configuration-file or a BLS snippet to be processed.

A configuration section in a zipl configuration-file is specified through its section name. A BLS snippet is specified through the value of its title option within the snippet.

Command line:
-d <dump_device>[,<size>]
--dumpto=<dump_device>[,<size>]

zipl configuration-file:
dumpto=<dump_device>[,<size>]
Specifies the DASD partition, SCSI disk partition, or tape device to which a dump is to be written after IPL.

The optional size specification limits the amount of memory to be dumped. The value is a decimal number that can optionally be suffixed with K for kilobytes, M for megabytes, or G for gigabytes. The value is rounded to the next megabyte boundary. If you limit the dump size below the amount of memory that is used by the system to be dumped, the resulting dump is incomplete. If no limit is provided, all of the available physical memory is dumped.

See Preparing a DASD device, SCSI disk, or channel-attached tape dump device and Using the Dump Tools on Red Hat® Enterprise Linux 8.6, SC34-7718 for details.

Command line:
--environment

Specifies the location of a zipl environment file, see zipl environment - Variables for the kernel command line. The default location is /etc/ziplenv.
Command line:
-h
--help
Displays help information.
Command line:
-i <image>[,<image_addr>]
--image=<image>[,<image_addr>]

zipl configuration-file:
image=<image>[,<image_addr>]

BLS snippet:
linux <image>
Specifies the location of the Linux® kernel image on the file system.

In command-line mode or in a zipl configuration-file section you can optionally specify a memory location after IPL. The default memory address is 0x10000.

See Preparing a boot device for details.

Command line:
-k auto
--kdump=auto

zipl configuration-file:
kdump=auto
Installs a kdump kernel that can be used as a stand-alone dump tool. You can IPL this kernel in an LPAR or guest virtual machine to create a dump of a previously running operating system instance that has been configured with a reserved memory area for kdump. For Linux, this memory area is reserved with the crashkernel= kernel parameter.

See Preparing a boot device for details.

Command line:
-m <menu_name>
--menu=<menu_name>
Specifies the name of the menu that defines a menu configuration in the configuration file (see Defining menu configurations).
Command line:
-M <dump_device_list>[,<size>]
--mvdump=<dump_device_list>[,<size>]

zipl configuration-file:
mvdump=<dump_device_list>[,<size>]
Specifies a file with a list of DASD partitions to which a dump is to be written after IPL.

The optional size specification limits the amount of memory to be dumped. The value is a decimal number that can optionally be suffixed with K for kilobytes, M for megabytes, or G for gigabytes. The value is rounded to the next megabyte boundary. If you limit the dump size below the amount of memory that is used by the system to be dumped, the resulting dump is incomplete. If no limit is provided, all of the available physical memory is dumped.

See Preparing a multi-volume dump on ECKD DASD and Using the Dump Tools on Red Hat Enterprise Linux 8.6, SC34-7718 for details.

Command line:
-n
--noninteractive

n/a
Suppresses all confirmation prompts (for example, when preparing a DASD or tape dump device).
Command line:
-p <parmfile>[,<parm_addr>]
--parmfile=<parmfile>[,<parm_addr>]

zipl configuration-file:
parmfile=<parmfile>[,<parm_addr>]
In a boot configuration, specifies the location of a kernel parameter file.

You can specify multiple sources of kernel parameters. For more information, see How kernel parameters from different sources are combined.

The optional <parm_addr> specifies the memory address where the combined kernel parameter list is to be loaded at IPL time.

Command line:
-P <parameters>
--parameters=<parameters>


zipl configuration-file:
parameters=<parameters>


BLS snippet:
options <parameters>
In a boot configuration, specifies kernel parameters.

Individual parameters are single keywords or have the form key=value, without spaces. If you provide multiple parameters, separate them with a blank and enclose them within single quotation marks (') or double quotation marks (").

You can specify multiple sources of kernel parameters. For more information, see How kernel parameters from different sources are combined.

Command line:

-r <ramdisk>[,<initrd_addr>]
--ramdisk=<ramdisk>[,<initrd_addr>

zipl configuration-file:
ramdisk=<ramdisk>[,<initrd_addr>

BLS snippet:
initrd <ramdisk>
Specifies the location of the initial RAM disk (initrd) on the file system.

In command-line mode or in a zipl configuration-file section you can optionally specify a memory location after IPL.

If you do not specify a memory address, zipl investigates the location of other components and calculates a suitable address for you.
-S <mode>
--secure=<mode>

secure=auto|0|1
In an LPAR boot configuration, controls the format of the boot data that zipl writes to a SCSI IPL disk or NVMe IPL device. You can specify the following values for <mode>:
auto
Uses the secure-boot enabled format if the zipl command is issued on a mainframe with secure-boot support. This is the default.
1
Enforces the secure-boot enabled format regardless of mainframe support. Use this option to prepare boot devices for systems other than the one you are working on. Disks with this format cannot be booted on machines z14 or earlier.
0
Enforces the traditional format, that does not support secure boot, regardless of mainframe support. Disks with this format can be booted on all machines but cannot be used for secure boot.
For more information about secure boot, see Secure boot.
Command line:
-t <directory>
--target=<directory>

zipl configuration-file:
target=<directory>
Specifies the target directory where zipl creates boot-relevant files. The boot loader is installed on the disk that contains the target directory.
Command line:

--targetbase=<targetbase_node>


zipl configuration-file:
targetbase=<targetbase_node>
For logical boot devices, specifies the device node of the base device, either by using the standard device name or in form of the major and minor number, separated by a colon (:).

See Using base device parameters for a logical boot device for details.

Command line:
--targetblocksize=<targetblocksize>


zipl configuration-file:
targetblocksize=<targetblocksize>
For logical boot devices, specifies the bytes per block of the base device.

See Using base device parameters for a logical boot device for details.

Command line:
--targetgeometry=<cylinders>,<heads>,<sectors>

zipl configuration-file:
targetgeometry=<cylinders>,<heads>,<sectors>
For logical boot devices that map to ECKD type base devices, specifies the disk geometry of the base device in cylinders, heads, and sectors.

See Using base device parameters for a logical boot device for details.

Command line:
--targetoffset=<targetoffset>


zipl configuration-file:
targetoffset=<targetoffset>
For logical boot devices, specifies the offset in blocks between the start of the physical device and the start of the logical device.

See Using base device parameters for a logical boot device for details.

Command line:
--targettype=<type>

zipl configuration-file:
targettype=<type>
For logical boot devices, specifies the device type of the base device.

See Using base device parameters for a logical boot device for details.

Command line:
-T <tape_node>
--tape=<tape_node>

zipl configuration-file:
tape=<tape_node>
Specifies the tape device where zipl installs the boot loader code.
Command line:
-v
--version
Prints version information.
Command line:
-V
--verbose
Provides more detailed command output.

If you call zipl in configuration file mode without specifying a configuration file, the default /etc/zipl.conf is used. You can change the default configuration file with the environment variable ZIPLCONF.

The default directory for files with BLS snippets is /boot/loader/entries. You can change this default with the BOOT environment variable.