On Wednesday, 01/21/2009 at 02:39 EST, David Boyes <[email protected]> wrote: > I also really prefer to let VM manage the actual cyl 0. That may be just > that I'm ancient and weird, but that way, there's absolutely zero chance > that something weird in Linux will cause something unpleasant to happen to a > disk that some other OS cares about, and there's zero chance of some yoyo > creating duplicate volids on the physical system, which could impact the > operation of the entire environment (cf the discussion about what order > multiple DRCT areas get interpreted if you want to see how random that can > get)
z/VM presumes that you do not have any duplicate volids for any volid that appears in SYSTEM CONFIG. If you allow duplicate volids, then you place the system at risk since the system may mount the wrong volume during IPL. <A Voice, off-stage> : 11. Thou shalt Not give cylinder 0 unto thine untrusted guests 12. Thou may ignorest #11 if thou will use OFFLINE_AT_IPL and ONLINE_AT_IPL to ensure that only the RDEVs desired by thee are processed in SYSTEM CONFIG. Let not the serpent of Convenience sway you onto a Dark path of Corruption. Alan Altmark z/VM Development IBM Endicott ---------------------------------------------------------------------- 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
