>>> On 6/22/2009 at 12:31 PM, Dave Jones <d...@vsoft-software.com> wrote: > Hi, Mark. > > Mark Post wrote: >>>>> On 6/22/2009 at 11:41 AM, Dave Jones <d...@vsoft-software.com> >>>>> wrote: >> -snip- >>> The real problem is that z/VM does not virtualize FCP-attached disk >>> like it can do for ECKD and FBA devices....the WWPN and LUN values >>> are "real" ones, and can not be shared across virtual machines. >> >> Of course they can be, otherwise clustering wouldn't be possible at >> all. >> > How so, then? What I mean here is that FCP attached SCSI devices can not > be "shared" across virtual machines the way CP handles sharing of 3390 > DASD, via the LINK statement.
That's what EDEVs are for. > CP is not involved at all when Linux guests, as near as I can > tell.....if two or more Linux guests share the same real SCSI device > (same WWPN and LUN), then it's up to the guests themselves to manage access. Correct, and that's a very well known and understood technology, whether using direct access by all systems involved or iSCSI. Mark Post ---------------------------------------------------------------------- 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
