On Thu, 06 Jan 2011 16:10:36 -0500 (EST), Richard Troth wrote: > > The "problem" is that one cannot boot from an unpartitioned CKD disk > (LDL) even though one can boot from an unpartitioned FBA disk. > Partition tables are not required for other disks and bootstraps. Why > should they be required for mainframe disks and bootstraps?
The Linux kernel does not consider an LDL-format disk to be "unpartitioned". If you format a disk with dasdfmt using "-d ldl" (and other appropriate parameters), then the disk has been implicitly partitioned, as far as the Linux kernel is concerned. Assuming CKD DASD, the implicit partition will begin with the fourth physical block. (The first two blocks are reserved for IPL records, the third block is the volume label.) I haven't tested your exact scenario, but here's what I have tested. I have a Linux machine that runs in a virtual machine under z/VM. It has four disks, as follows: device block mount number special point file ------ ------- ----- 0200 /dev/dasda /dev/dasda1 / 0201 /dev/dasdb /dev/dasdb1 /boot 0202 /dev/dasdc /dev/dasdc1 /home 0203 /dev/dasdd /dev/dasdd1 swap All four of the disks are CMS reserved minidisks. All of them use the DIAG driver except 0201, which uses the ECKD driver. The boot device is 0201. Linux is started by IPL 0201 It works great. I've been doing it for years. What's the problem? (0201 has to use the ECKD driver because zipl does not support writing IPL records to a device controlled by the DIAG driver) -- .''`. Stephen Powell : :' : `. `'` `- ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/