NAME¶
chreipl - change the re-IPL configuration for Linux on System z
SYNOPSIS¶
chreipl [TARGET] [OPTIONS]
DESCRIPTION¶
Use the
chreipl tool to modify the re-IPL configuration for Linux on
System z. You can configure a certain boot device and, for zipl boot menu
configurations, the boot menu entry that will be used for the next reboot.
Also kernel parameters for the next Linux kernel can be defined.
Initial program load (IPL) is the mainframe synonym for what is called
"boot" under Linux. Accordingly re-IPL can be translated to
"reboot" in the non-mainframe context.
Normally for reboot the last IPL device is used to restart the system. To reboot
from another IPL device, you first have to change the re-IPL settings with
chreipl and then run the
reboot(8) command.
All settings made with
chreipl are preserved over reboots until they are
changed again.
TARGET¶
The first argument specifies the re-IPL target:
- - ccw:
- Specify a DASD CCW device for reboot
- - fcp:
- Specify a FCP device for reboot
- - nss:
- Specify a named saved system (NSS) for reboot
- - node:
- Specify a device for reboot using a device node or directory
If the target specification is non-ambiguous it can be omitted. See section
AUTOTARGET for more information. Ambiguous setups are very rare, e.g.
the name of a device node theoretically could be the same as a bus-ID.
OPTIONS¶
- -p or --bootparms
- Specifies boot parameters for the next reboot. The boot parameters which
are typically kernel parameters are appended to the kernel parameter line.
If you specify the boot parameters with a leading equal sign (=), the boot
parameters replace all parameters on the kernel parameter line. To remove
boot parameters, specify an empty string for this option.
Depending on the chreipl target a different maximum number of characters is
allowed for boot parameters. Under LPAR it is not possible to specify boot
parameters for the ccw target.
Note: When replacing all parameters, you might inadvertently omit
parameters that the boot configuration requires. Read /proc/cmdline
to find out with which parameters a running Linux instance has been
started.
- -h or --help
- Print help information, then exit.
- -v or --version
- Print version information, then exit.
All other options are specific to the re-IPL target and are discussed below in
the respective section. For a more detailed description of the Linux on System
z IPL mechanisms see
zipl.conf(6). The mandatory options (e.g. device,
wwpn, lun, etc.) can also be specified as positional parameters.
AUTOTARGET¶
For the ccw, fcp, and node targets
chreipl can find automatically the
correct re-IPL target. To do this, omit the re-IPL target parameter and start
specifying the required positional parameters.
Examples:
1. Next time reboot from the DASD device /dev/dasda using the first boot
configuration:
# chreipl /dev/dasda -L 1
2. Next time reboot from the CCW device with the bus-ID 0.0.7e78 and empty
loadparm:
# chreipl 0.0.7e78
3. Next time reboot from the SCSI disk with FCP bus-ID 0.0.1700, WWPN
0x500507630300c562, and LUN 0x401040b300000000. In addition to that append
kernel parameter "mem=" to restrict memory to 512 MB:
# chreipl 0.0.1700 0x500507630300c562 0x401040b300000000 -p
"mem=512M"
ccw¶
Use the ccw re-IPL target for DASD devices that are accessed by the hardware
using channel command word (CCW) channels.
- -d or --device
- Specifies the CCW bus-ID. If the bus-ID starts with "0.0." this
prefix can be omitted and the four digit short notation can be used (e.g.
5000 is the same as 0.0.5000).
- -L or --loadparm
- Specifies an entry in the zipl(8) boot menu. If this option is
omitted, the default menu entry is used.
Examples:
1. Next time reboot from the CCW device with the bus-ID 0.0.7e78 and empty
loadparm:
# chreipl ccw 0.0.7e78
2. Next time reboot from the CCW device with the bus-ID 0.0.7e78 using the first
entry of the zipl boot menu:
# chreipl ccw -d 0.0.7e78 -L 1
fcp¶
Use the fcp re-IPL target for SCSI disks that are accessed by the hardware using
Fibre Channel Protocol (FCP) channels.
- -d or --device
- Specifies the bus-ID of the FCP adapter that should be used to access the
SCSI re-IPL device. If the bus-ID starts with "0.0." this prefix
can be omitted and the four digit short notation can be used (e.g. 5000 is
the same as 0.0.5000).
- -w or --wwpn
- Specifies the world wide port name (WWPN) for the FCP attached SCSI disk.
- -l or --lun
- Specifies the logical unit number (LUN) for the FCP attached SCSI disk.
- -b or --bootprog
- Specifies an entry in the FCP boot configuration by defining the IPL boot
program selector. If omitted, '0' will be used.
Examples:
1. Next time reboot from the SCSI disk with FCP bus-ID 0.0.1700, WWPN
0x500507630300c562, LUN 0x401040b300000000, and boot program selector 0:
# chreipl fcp 0.0.1700 0x500507630300c562 0x401040b300000000
2. Use same configuration as (1) but choose boot program selector 2 and use
options instead of positional parameters:
# chreipl fcp -d 0.0.1700 -w 0x5005076... -l 0x401040b3... -b 2
nss¶
Use the nss re-IPL target to specify z/VM named saved systems (NSS) for reboot.
- -n or --name
- Specifies the name of the NSS.
Examples:
Use the NSS named LINUX1 for the next reboot:
# chreipl nss LINUX1
node¶
You can identify DASD or SCSI re-IPL devices indirectly through a device node or
directory. The chreipl tool then determines the information that you would
otherwise have to specify with the ccw or fcp target.
Examples:
1. Next time reboot from the DASD device /dev/dasda:
# chreipl node /dev/dasda
2. Next time reboot from the SCSI disk /dev/sda:
# chreipl node /dev/sda
3. Next time reboot from the device where directory /mnt/boot is located:
# chreipl node /mnt/boot
SEE ALSO¶
lsreipl(8),
zipl(8),
zipl.conf(5),
reboot(8)