Hello, following feedback from the last SHARE conference, it seems that not many users are aware of the integrated multiboot/bootmenu feature of the zipl bootloader. As this function can be rather useful in situations where newly installed kernels won't boot, I'd like to give a quick introduction.
Starting with version 1.3.0, zipl supports the following: a) selecting a kernel configuration from a predefined set (menu) at IPL time (SCSI and DASD) b) providing additional kernel parameters at IPL time (DASD only) For an in-depth explanation on how to use this feature, please see the respective man-pages for zipl and zipl.conf, which are part of the s390-tools package (I took the liberty to attach the relevant parts to the end of this posting). The most current version of zipl can be obtained as part of the s390-tools package: http://oss.software.ibm.com/linux390/s390-tools-1.3.1-april2004.shtml The multiboot feature should also be part of current Linux distributions like SUSE's SLES9. I hope this information might prove useful. Regards, Peter Oberparleiter P.S.: Integration of VMPARM support is being worked on. ---------- excerpt from the man page for zipl.conf: Example configuration: # An example for a zipl.conf file [defaultboot] defaultmenu = menu1 [linux] target = /boot image = /boot/image parameters = "root=/dev/dasda1 console=ttyS0" [test] target = /boot image = /boot/image-test parmfile = /boot/parmfile-test :menu1 target = /boot 1 = linux 2 = test default = 1 prompt = 1 timeout = 0 Boot menu The zipl tool provides a boot menu function which enables a user to choose a boot configuration and to add extra kernel command line param- eters at IPL time (only available for DASD disk devices). Before a boot menu can be used, a menu section has to be defined (see example configuration) and installed. Configurations included in the menu section are subsequently identified by their assigned number. If the ’prompt’ setting of the menu section is set to 1, a menu text will be displayed during IPL and the boot program will wait for user input: zIPL interactive boot menu 0. default (linux) 1. linux 2. test Please choose: The menu prompt expects the configuration number as input. Typing ’0 will start the default configuration. Additional kernel parameters can be specified by supplying them after the configuration number, sepa- rated by a blank character. Example input: 2 mem=128m maxcpus=1 This will start configuration 2 and append the string "mem=128m maxc- pus=1" to the existing kernel command line. Note that the extra parame- ters are only temporary and won’t be saved for the next IPL process. Note also that the selected configuration number will be available to the init process through the environment variable named BOOT_IMAGE. If the ’timeout’ option has been used, the boot menu will automatically start the default configuration after the specified number of seconds has passed without user input. VM users need to prefix all input with the VM VINPUT command, e.g. type ’#cp vinput vmsg 0’ to boot the default configuration. Another way of selecting a configuration without the interactive menu is by specifying its number using the IPL ’loadparm’ function, e.g.: #cp ipl 0192 loadparm 2 In case the specified number does not correspond to a valid configura- tion, the boot process will abort with a disabled wait state (address code 0x300). The loadparm function is available even if the menu has been deacti- vated by setting ’prompt’ to zero or by installing only a single con- figuration. The menu can then be temporarily activated by passing the string ’prompt’ via the loadparm function: #cp ipl 0192 loadparm prompt OPTIONS prompt = 0/1 (menu only) Menu section: Setting this option to 1 activates the interactive boot menu which can be used to select a configuration at boot time (DASD disks only). See previous section for a detailed description of the boot menu. The default value for ’prompt’ is 0. timeout = menu-timeout (menu only) Menu section: Specify a timeout interval in seconds after which the interac- tive boot menu will automatically select the default boot con- figuration. Setting this value to 0 or providing any user input at boot time will deactivate the timeout mechanism. The default value for ’timeout’ is 0. -- Peter Oberparleiter Linux on zSeries Development IBM Development Lab, Boeblingen/Germany ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
