I have meant to bring this up to the list before now, but since you mention it...
I use the "clone a golden image" methodology. I've used DDR, which always works, and I've used dasdfmt and dd, which sometimes results in an unstable system. I can't pin it down exactly, but I think it happens when I repurpose minidisks that have had Linux filesystems on them previously. The first symptom I see is segmentation faults in YaST. When I CPFMTXA the minidisk before using the dasdfmt and dd cloning method, I don't have the problem. Therefore, I always CPFMTXA the dasd first. Terry, I would not use DEDICATE. I like to preserve cyl 0 because I know z/VM and z/OS understand it. ________________________________ From: The IBM z/VM Operating System [mailto:[email protected]] On Behalf Of Martin, Terry R. (CMS/CTR) (CTR) Sent: Wednesday, March 24, 2010 1:54 PM To: [email protected] Subject: initializing z/Linux disks Hi I have a question. What I have been doing up to this point for a new z/Linux guest build is, not necessarily in this order and does not necessarily include all steps but, Crave out the DASD for the z/Linux guest Init the DASD using CPFMTXA putting a label on the disk Setting up the Directory entry for the new guest, which includes specifying the MDISK for all of the DASD for the guest. We back up our z/Linux guests on the z/OS side with DFDSS. My question is since when we Kick Start the new z/Linux guest and it initializes the DASD during this process is there any compelling reason for me to initialize the DASD up front before the guest is Kick Started for the first time basically doing a double INIT? If not I assume then I would replace the MDISK statements in the Directory entry with DEDICATE statements for each one of the DISKS. We do not share DASD between guests here so what is defined to the guest belongs to that guest only. Is there anything to be aware of by changing to DEDICATE statements from MDISK statements? My only concern is with the DFDSS backups that I do on the z/OS for the guests. I am not sure if it matters or not to DFDSS whether the pack was initialized via CPFMTXA or z/Linux during the kick start process? Thank You, Terry Martin Lockheed Martin - Citic z/OS and z/VM Performance Tuning and Operating Systems Support Office - 443 348-2102 Cell - 443 632-4191 cid:[email protected]
