LDL format was the first format used by Linux. It was quickly replaced by CDL format. The main difference is that a disk in CDL format is seen as being full by all other operating systems (VM, VSE OS/390). However, they see a LDL fromat disk as being empty. Thus if you are going to run anything other than Linux on your Z196 you must make a special effort to keep the other systems from over writing the Linux disks in LDL format. The other systems will not automatically over write a CDL format disk as they think it is already full of data that can not be deleted.
DIAG works with CDL format. As DIAG was added to Linux after CDL format was in wide use, I don't know if support for LDL was added to DIAG. (It probably was.) The only advantage to LDL is you may be able to have 1 additional 4K block of Linux data on the disk. There is no reason why you can't put /boot on a DIAG disk. There are some restrictions to where you can put /boot. -- Stephen Frazier Information Technology Unit Oklahoma Department of Corrections 3400 Martin Luther King Oklahoma City, Ok, 73111-4298 Tel.: (405) 425-2549 Fax: (405) 425-2554 Pager: (405) 690-1828 email: stevef%doc.state.ok.us On 1/3/2011 9:59 AM, Samir Reddahi wrote:
Disks are currently formatted with cdl. I've read that cdl and DIAG can't work together so the disks have to be formatted to another format. We will be migrating to a new Z196 and a new DS8800, so I can use the downtime to switch the logical volume to an LV with DIAG disks a couple of questions: 1) Are there any disadvantages of formatting disks as ldl instead of cdl? 2) Is it true that /boot directory has to be located on a non-DIAG disk?
-- Stephen Frazier Information Technology Unit Oklahoma Department of Corrections 3400 Martin Luther King Oklahoma City, Ok, 73111-4298 Tel.: (405) 425-2549 Fax: (405) 425-2554 Pager: (405) 690-1828 email: stevef%doc.state.ok.us ---------------------------------------------------------------------- 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/