My original question was:
> I would like to hear from anybody that has experience (good or bad)
> with providing an on-line optical archiving service from a Dec Alpha.
>
> I am particularly interested in the 5.25 Inch HP Surestore Boxes with
> software that provides some caching before writing to the optical
> media.
>
> I know DEC provide OSMS but as far as I know this is only a way of
> managing the optical media and making it available to DEC Unix, the
> user would still be writing directly to the Optical media which is
> slow. I need to provide a solution to many systems so NFS is my
> preferred choice.
>
I have received a number of very useful replies, the consensus seems to be
using Dec RW drives with Dec's HSM software although one reply was not so
favourable of the early product. I intend to evaluate the DEC solution
although the HSM software seems very expensive.
Thanks to those that replied (listed at the beginning of each reply), here
is the summary:
sarasin_at_yosemite.cop.dec.com
You may want to check out POLYCENTER Hierarchical Storage Management (HSM)
Solution for
DEC OSF/1, Version 1.2A The SPD can be found at
ftp://ftp.digital.com/pub/Digital/info/SPD/50-71-05.txt
HSM uses an ADVFS file system to front end the optical storage. To the
users the storage looks like one big disk. Since you are using part of your
normal file system to front end your Optical Jukeboxes the system has very
nice responce times. Here is a short clip from the SPD. I have installed
this at several sites with very good results. NFS clients mount the
magnetic disk front end and HSM does the rest. Also since the storage
is front ended by ADVFS if you have a system crash you can recover your
optical storage very quickly.
Joe Hatchel <jhatchel_at_pharmaco.com>
I too am interested in such an optical disk solution for Digital
Unix. In the past, DECs optical products were only available on VMS which
we don't speak here. I tried a do-it-yourself setup of a MaxOptix drive on
a DECstation with disasterous results. Very, very slow and the filesystem
would occasionally get corrupted when adding to the disk. Needless to say
not good features for an archiving system trying to store >20MB /day/system
for 10-20 systems. I'd be interested in any responses you receive and what
you decide to go with. We plan to implement some time of system early next
year.
Tom Barkanic <intrepid!tb_at_uunet.uu.net>
We have two optical jukebox systems. One is from Pinnacle Systems (HP box)
running off a Sparc. The other is a DEC RW510 (HP box) running of a DEC
Alpha. Both jukeboxes have two drives, hold 32 platters and look
identical. With the DEC system we also got their SCSI CAM and HSM software.
With the software we can access the platters individually as UFS disks or
with the HSM software automatically archiving and unarchiving files. With
the HSM software the user always reads and writes to magnetic media and the
software takes care of the optical media.
sherman_at_pet.wustl.edu
We have been interested in a CD-R and CD-Jukebox system from Young Minds.
You can store 25 Tb of data for approximately 50000 U.S. Dollars with
database software indexing right on the CD. CD's that hold 600 Mbytes cost
8 US dollars (5 pounds :) and the capacity of a CD is expected to increase
to 4-8 Gbytes per CD.
The phone number for Young Minds in the U.S. is (909)335-1350. Young Minds
is the only company that I know of that handles Unix platforms for the past
couple of years.
Don Weyel <weyel_at_balsa.bme.unc.edu>
We have an HP Model 20LT Optical Disk Libary that serves several Alphas
(OSF versions between 2.0 and 3.2). It has been a headache since the day
it was purchased. I'm relatively new here, but the system was purchased by
a faculty member who made the best decision he could under trying
circumstances, but who now rues the day that he bought it. The software
that drives this box has not been upgraded past OSF 3.0; subsequently, we
have not upgraded its DEC 3000/600 server past 2.0 (that is about to
change). We have problems with odisk hangs and system crashes as a result
of odisk access problems. We've even considered buying a little HP box to
act as an odisk NFS server.
As for the caching software, we use Qstar, and it's another source of
problems for us. Occasionally, the cache becomes corrupted and
subsequent access to certain optical disks can hang the NFS link, or worse.
If we were to do it over again, I think we would consider a single vendor
solution. So, if you want to use HP optical disks, I suggest an HP server
and HP software.
Knut.Hellebo_at_nho.hydro.com
We tried the DEC Polycenter HSM solution together with a optical jukebox.
No good ! Because we ran NetWorker nightly all files backed up got their
accesstimes updated thus screwing up the whole HSM concept (files that
really should be rolled out did not). Also when running 'full' backup this
of course jammed the system because files archived were rolled back when
being backed up thus forcing files that should not be archived to be rolled
out (the disks were filling up). The concept was OK, though, and if they've
managed to correct the early flaws we saw it could be it is a nice product.
Thanks again
Gary Arnold
Head of Systems
Horticulture Research International
Gary.Arnold_at_HRI.BBSRC.AC.UK
Received on Thu Nov 02 1995 - 15:08:36 NZDT