Thanks to the following who replied to my queries about the
above:
Jay Maynard jmaynard_at_admin5.hsc.uth.tmc.edu
Dave Golden golden_at_falcon.invincible.com
Mike Crowley mcrowley_at_mhc.mtholyoke.edu
William Kuderka wkuderka_at_totaltec.com
Edward Baily ed_at_pigdog.niehs.nih.gov
Todd Acheson acheson_at_oak.cats.ohiou.edu
Marco Luchini m.luchini_at_ic.ac.uk
Alan Rollow alan_at_nabeth.cxo.dec.com
Ryan Ziegler zieglerr_at_novachem.com
My questions were:
> 1. Do I have to take the system down and reconfigure if I want
> to add extra disks? Does this mean I can only use preconfigured
> disks as hot-swaps?
Answer:
Yes, but there is not hot-swap capability with JBOD. You
have to reconfigure to add more disks.
> 2. Is it necessary to use the RAID software to initialize the
> disk (which takes ages) if I'm going to disklabel it from
> DEC Unix after?
Some said yes, some said they weren't sure for JBOD. Marco
suggested turning off write-thru to speed things up and turning it on
again after.
> 3. After setting up these JBOD disks, trying to disklabel them
> with:
>
> # disklabel -R -r re1 user-config rz28b
> partition c extends past end of disk by 144 sectors, truncate? [n]:
>
> Has initializing this disks with the utility made these disks smaller
> or has the rz28b become something else?
Mike explained that even with JBOD, you're creating a volume and
its not seen by the system as an rz28 or rz29. I've had three basic
disk configs in the past which I've kept in files and used to label
the disk with disklabel -R. Dave told me to use:
disklabel -wr re# SWXCR
I checked /etc/disktab and there's an entry for SWXCR. You can
also use re instead of SWXCR. William suggested using:
disklabel -rw re# rzxx
in order to force the OS to query the controller for the label info.
Ryan and Todd mentioned a GUI swxcrmgr utility. I don't
appear to have this. Dave asked if I had the StorageWorks RAID
Array 230 book. I haven't but I do have the 200 version. We
bought the controller and software back some time ago when
we were going to (continue to) run OpenVMS on AXP before moving to
OSF/1. Maybe my book (and software) is out of date.
The majority expressed satisfaction with the SWXCR RAID controller.
The config and initialization is a pain but you shouldn't have to resort
to it much. The majority queried why I was using JBOD at all when I
could be taking advantage of full RAID capabilities (RAID 5). I admit
I was expecting to have disks of the same config which I could swap
around whether the StorageWorks cabinet was on a SWXCR controller
or not. As this is not the case, then on reflection
the RAID advocatees are right!
Thanks again to all.
Ray
--
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Received on Tue May 21 1996 - 16:19:53 NZST