I guess the point I was trying to make somewhat imperfectly is that while the Linux guest might be able to access CKD disks and use SCSI protocols that is all emulated by z/VM so it's difficult to see the advantages of what the OP is asking.
On Wed, Dec 18, 2019, 12:39 AM Mike Schwab <mike.a.sch...@gmail.com> wrote: > You will need to convert to using Linux containers without the z/VM > layer and FCP to open system volumes. I did this on ESS F20s, should > be similar for DS8xxx. > > On Tue, Dec 17, 2019 at 2:44 AM Peter <dbajava...@gmail.com> wrote: > > > > CKD are well supported for Linux guest. > > > > But having FBA disk to linux guest will improve any sort of performance ? > > > > On Tue, 17 Dec, 2019, 12:32 PM Laurence Chiu, <lch...@gmail.com> wrote: > > > > > Slightly outside my area of knowledge but since z/VM is the OS that is > > > attached to the DS8K, it's doing the physical IO. And this is usually > > > FICON. > > > > > > The Linux guest is being provided a virtual disk from z/VM so the disk > > > protocol is probably not relevant. Plus I don't think a Linux guest can > > > actually see a CKD volume - it would all look ike FB. > > > > > > Others feel free to chip in here > > > > > > On Tue, Dec 17, 2019 at 4:45 PM Peter <dbajava...@gmail.com> wrote: > > > > > > > I believe giving a dasd 3390(CKD) to linux guest and internally it > > > converts > > > > that into SCSI. > > > > > > > > So having SCSI alone for Linux guest would be better interns of > > > performance > > > > ? > > > > > > > > On Tue, 17 Dec, 2019, 12:54 AM Laurence Chiu, <lch...@gmail.com> > wrote: > > > > > > > > > I asked my z/VM and DS8K person this question and he wasn't sure > what > > > you > > > > > were asking. > > > > > > > > > > He said he defines all the storage on his ds8k box as CKD though he > > > could > > > > > have chosen fixed block and assigns all that storage to the z/vm > host. > > > > > > > > > > For each Linux instance that requires storage he just carves out > the > > > hunk > > > > > of storage on Z/VM and assigns it to the Linux guest . > > > > > > > > > > SCSI is irrelevant because the Linux guest is virtual and doesn't > need > > > to > > > > > know about the disk protocol. And his z/VM host is connected via > > > FICON. > > > > > > > > > > He said the only time one might need to go back to the ds8k is if > some > > > of > > > > > the storage on that box hadn't been defined and needed to be > redefined > > > > and > > > > > then attached to the z/vm host. But he's never had to do that in 10 > > > years > > > > > of running that system. > > > > > > > > > > > > > > > > > > > > On Tue, Dec 17, 2019, 7:28 AM Peter <dbajava...@gmail.com> wrote: > > > > > > > > > > > Hello, > > > > > > > > > > > > Could someone please recommend a manual which describes step by > step > > > > > > procedure to define SCSI on DS8K. > > > > > > > > > > > > I need this procedure to define SCSI disk for my Linux guest > running > > > on > > > > > > zVM. > > > > > > > > > > > > Peter > > > > > > > > > > > > > > > ---------------------------------------------------------------------- > > > > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > > > > send email to lists...@listserv.ua.edu with the message: INFO > > > IBM-MAIN > > > > > > > > > > > > > > > > > ---------------------------------------------------------------------- > > > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > > > send email to lists...@listserv.ua.edu with the message: INFO > IBM-MAIN > > > > > > > > > > > > > > ---------------------------------------------------------------------- > > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > > send email to lists...@listserv.ua.edu with the message: INFO > IBM-MAIN > > > > > > > > > > ---------------------------------------------------------------------- > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > > > > > > > ---------------------------------------------------------------------- > > For IBM-MAIN subscribe / signoff / archive access instructions, > > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > > > > -- > Mike A Schwab, Springfield IL USA > Where do Forest Rangers go to get away from it all? > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
