SSA Managers Survey

I posted my survey to the Sun Managers mailing list, as well as to the Usenet newsgroups comp.sys.sun.admin and comp.sys.sun.hardware.

• Survey
• Responses
• Summary

From: Margarita Suarez 
Date: Tue, 19 Mar 96 11:09:12 EST
To: sun-managers@ra.mcs.anl.gov, comp.sys.sun.admin, comp.sys.sun.hardware
Subject: SPARCstorage Array Survey

Hi Sun Managers,

If you manage (or used to manage) Sun SPARCstorage Arrays, please read this.

We've been using SSA's at our site for about a year and a half now.  Our
first 3 SSA's ran striped, mirrored (RAID 0+1) volumes for a year.  Last
summer, we bought 4 more and converted our filesystems over to RAID 5.
We've had various hardware and software problems with our arrays, enough
to make us seriously consider buying an Auspex to replace them all.  I'd
like to find out how folks are using their SSA's, and what kinds of
problems (if any) they have encountered.

Our problems have been of the following sorts:
1) flaky hardware - we have had to replace 2 controllers, one suspect
   power supply, and at least 3 disk trays.  our first 3 arrays were
   plagued with the ONLINE/OFFLINE problems which were fixed by
   replacing optical fibre hardware (FOM's, SOC cards, etc.) we have more
   than 150 disks and we've seen more than 10% fail in the last year.
   the problems have occurred on all types of Sun SSA disks:
   1gig (conner and seagate) and 2gig (seagate barracuda).
2) software problems - the Veritas volume manager often does not employ
   hot spares, based on a fuzzy interpretation of "disk failure."  Sun tells
   us the next release of volume manager is supposed to fix this.
3) RAID5 problems - we have lost entire RAID5 volumes mysteriously with
   a single disk failure, or with no disk failure at all.   The symptom
   is that the filesystem cannot be fsck'ed -- thousands of inodes are
   misplaced.  it looks like something just scribbled all over the filesystem.
   dunno if it was the controller, RAID 5 driver, kernel, or what.

Problems 1) and 3) may have been caused by dirty power.  We have been
putting our arrays on UPS's to clean the power.  We haven't lost a disk
in a whole week :-)

What I want to know from you is:

1) How many arrays are you running?  For how long? What models?  How many
   disks per array?  What size?
2) Are your SSA's Single or Dual-Ported? What kinds of host processors?
3) Do you use uninterruptible power supplies?
4) Have you had hardware problems?  If so, what kinds?
5) How are you running your arrays?  Raw disks (/dev/dsk/cNtNdNsN)?
   Veritas Volume Manger or Solstice DiskSuite?  What RAID levels
   (concatenated, mirrored, striped, RAID 5), or as "managed" raw disks
   (/dev/vx/dsk/dg/rawvol)?
6) What version of Solaris OS and Array software are you running?
7) Do you use fast_writes (NVRAM cache)?  Do you use DRL or RAID 5 logging?
8) Have you had any trouble with the array software (managing disks, hot
   sparing, RAID "protection")?
9) How do you use your SSA's (database, NFS service, other)?  How is
   performance?
10) How satisfied are you with your SSA's?  Will you keep them?  Will you
    buy more?  Or will you buy an Auspex?

Please send your replies to me, and I will summarize.

Thanks for your time,

Margarita Suarez <marg@columbia.edu>
Columbia University
Academic Information Systems
UNIX Systems Group

Back to marg's Sun SPARCstorage Array Page