>>> On 1/31/2011 at 04:07 PM, Alan Altmark <[email protected]> wrote: > My turn to ask a question.... :-) > > I have a bunch of Model 54 disk volumes that contain not-quite-fullpack > n-minus-1-cyl minidisks. Some have 8 static PAVs, some have only 2. > > 1. I want to exploit virtual PAVs (MINIOPT/DEFINE PAVALIAS), as a lot of > I/O will be done to these volumes (multiple of them per guest).
I haven't actually played with PAVs, so I'm coming at this from about the same level of expertise. However, I thought PAVs were only of interest to Linux if the devices were dedicated, not minidisks. I thought PAVs for minidisks would be handled by z/VM itself. > 2. I want to set up LVM to use those PAVs. > 3. I want to be able to clone or recover the LVM to other volumes > 4. I want LVM to be insensitive to the number of PAVs, it being just a > performance improvement mechanism > 5. These are not-quite-fullpack n-minus-1-cyl minidisks If I'm remembering correctly, and z/VM does do all the work with PAV for minidisks, then 3-4 should be completely transparent to Linux. > Are there issues that will inhibit me from reaching my goal? For sure, if you were to use dedicated DASD, then you would need to set up multipathing for them. If z/VM doesn't do the heavy lifting for minidisks, then the same would hold true there. So, you would need to define the multiple paths to the various devices and tell LVM to use those multipathed names for the PVs, and exclude the "raw" device names in the LVM filters. I've never done that with ECKD or FBA volumes, so I can't be more specific about how to go about that. I believe it would mean that any clones or restores to other volumes might involve some manual intervention to get things looking "just so" to multipathd. Mark Post ---------------------------------------------------------------------- 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 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
