McKown, John wrote:
Please be kind. I don't have a z/Linux system around. But I know that you cannot share a filesystem between two z/Linux instances in read/write mode and hope to keep a usable filesystem (in the general case). I wonder why the dasd driver cannot (or does it?) implement an "ioctl" or some interface which the mount command could use to do a device reserve against the dasd device when mounted in read/write mode (or make it optional). Does anybody "partition" a 3390 into multiple filesystems, then use those filesystems on different z/Linux instances?
You can't share a partition if _anyone_ has write access to it. Writer writes where a reader's read and cached, and reader has an inconsistent view of the disk. Simplest, safest, is to mount ro everywhere, and when the disk needs to be updated, unmount (or take down) all readers and then allow the writer to remount rw, write, then remount to. Then, reenable all the readers. Doubtless VM allows you to do some mirror magic here. -- Cheers John -- spambait [EMAIL PROTECTED] [EMAIL PROTECTED] Tourist pics http://portgeographe.environmentaldisasters.cds.merseine.nu/ do not reply off-list ---------------------------------------------------------------------- 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
