Defining menu configurations

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

For DASD and SCSI devices, you can define a menu configuration. A menu configuration has a section identifier that consists of a menu name with a leading colon.

The identifier is followed by one or more lines with references to IPL configurations in the same zipl configuration-file or to BLS snippets. The menu configuration can also include one or more option lines.

target=<directory>

specifies a device where a boot loader is installed that handles multiple IPL configurations. For menu configurations, the target options of the referenced IPL configurations are ignored.

<i>=<configuration>

specifies a menu item. A menu includes one and more lines that specify the menu items.

<configuration> is the name of an IPL configuration that is described in the same zipl configuration-file, or it is the title of a BLS snippet. You can specify multiple boot configurations. For SCSI target devices, you can also specify one or more SCSI dump configurations. You cannot include DASD dump configurations as menu items.

<i> is the configuration number. The configuration number sequentially numbers the menu items, beginning with 1 for the first item. When initiating an IPL from a menu configuration, you can specify the configuration number of the menu item you want to use.

default=<n>

specifies the configuration number of one of the configurations in the menu to define it as the default configuration. If this option is omitted, the first configuration in the menu is the default configuration.

prompt=<flag>

for a DASD target device, determines whether the menu is displayed when an IPL is performed. Menus cannot be displayed for SCSI target devices.

For prompt=1 the menu is displayed, for prompt=0 it is suppressed. If this option is omitted, the menu is not displayed. Independent of this parameter, the operator can force a menu to be displayed by specifying prompt in place of a configuration number for an IPL configuration to be used.

If the menu of a menu configuration is not displayed, the operator can either specify the configuration number of an IPL configuration or the default configuration is used.

timeout=<seconds>

for a DASD target device and a displayed menu, specifies the time in seconds, after which the default configuration is IPLed, if no configuration has been specified by the operator. If this option is omitted or if 0 is specified as the timeout, the menu stays displayed indefinitely on the operator console and no IPL is performed until the operator specifies an IPL configuration.

secure=<mode>

In an LPAR boot configuration, controls the format of the boot data that zipl writes to a SCSI 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.

As for any configuration section, additional parameters might be required for logical boot devices.

Example

Figure 1 shows a sample configuration file that defines multiple configuration sections and two menu configurations.

Figure 1. Sample /etc/zipl.conf file

[defaultboot]
defaultmenu=menu1

# First boot configuration (DASD)
[boot1]
ramdisk=/boot/initrd
parameters='root=/dev/ram0 ro'
image=/boot/image-1
target=/boot

# Second boot configuration (SCSI)
[boot2]
image=/boot/mnt/image-2
ramdisk=/boot/mnt/initrd,0x900000
parmfile=/boot/mnt/parmf-2
target=/boot

# Third boot configuration (DASD)
[boot3]
image=/boot/mnt/image-3
ramdisk=/boot/mnt/initrd
parmfile=/boot/mnt/parmf-3
target=/boot

# Configuration for dumping to tape
[dumptape]
dumpto=/dev/rtibm0

# Configuration for dumping to DASD
[dumpdasd]
dumpto=/dev/dasdc1

# Configuration for multi-volume dumping to DASD
[multi_volume_dump]
mvdump=sample_dump_conf

# Configuration for dumping to SCSI disk
[dumpscsi]
dumpto=/dev/mapper/36005076303ffd40100000000000020c0-part1

# Menu containing the SCSI boot and SCSI dump configurations
:menu1
1=dumpscsi
2=boot2
target=/boot
default=2

# Menu containing two DASD boot configurations
:menu2
1=boot1
2=boot3
target=/boot
default=1
prompt=1
timeout=30

The following commands assume that the configuration file of the sample is the default configuration file.

Call zipl to use the default configuration file settings:
```
# zipl
```
Result: zipl reads the default option from the [defaultboot] section and selects the :menu1 section. It then installs a menu configuration with a boot configuration and a SCSI dump configuration.
Call zipl to install a menu configuration:
```
# zipl -m menu2
```
Result: zipl selects the :menu2 section. It then installs a menu configuration with two DASD boot configurations.
Call zipl to install a boot loader for boot configuration [boot2]:
```
# zipl boot2
```
Result: zipl selects the [boot2] section. It then installs a boot loader that loads copies of /boot/mnt/image-2, /boot/mnt/initrd, and /boot/mnt/parmf-2.
Call zipl to prepare a tape that can be IPLed for a tape dump:
```
# zipl dumptape
```
Result: zipl selects the [dumptape] section and prepares a dump tape on /dev/rtibm0.
Call zipl to prepare a DASD dump device:
```
# zipl dumpdasd -n
```
Result: zipl selects the [dumpdasd] section and prepares the dump device /dev/dasdc1. Confirmation prompts that require an operator response are suppressed.
Call zipl to prepare a SCSI dump device:
```
# mount /dev/sda1 /boot
# mount /dev/sda2 /dumps
# mkdir /dumps/mydumps
# zipl dumpscsi
# umount /dev/sda1
# umount /dev/sda2
```
Result: zipl selects the [dumpscsi] section and prepares the dump device /dev/sda1. The associated dump file is created uncompressed in directory /mydumps on the dump partition. If space is required, the lowest-numbered dump file in the directory is deleted.