vxva vs. ODS (was Re: RSM 2000 list)

[Klorese, Roger B.A.]

On Saturday, May 31, 1997 1:13 AM, Marc Philip Alexander Jordan St.-Gil
[SMTP:mstgil@unt.edu] wrote:
> I agree it's not simple.  To further your anology, "I don't mind going
> dutch treat for lunch, but I do mind being offered lunch and then being
> stuck with the full tab after we've both eaten."  What hacks me off is
> that _nowhere_ in the documentation that comes with either the SSA or the
> "VxVM lite" does it say "this version of VxVM _only_ works with the SSA
> you bought and if you _ever_ plan on adding another non-SSA array, you'd
> better just use SDS or plan on upgrading to "full VxVM"."  i.e. if Sun's
> going to bundle a "lite" version, the should at least put a warning label
> on it somewhere.  

As someone pointed out, the striping and RAID-5 restrictions ARE in the
docs.

In addition, though: you acquired a product called SPARCstorage Volume
Manager.  While it's based on technology called VERITAS Volume Manager,
it may or may not have any or all of the capabilities of any oher
product based on VERITAS Volume Manager.  The only place the feature set
of SPARCstorage Volume Manager is documented in a way that is relevant
to the decision process is in Sun's docs, including the SPARCstorage
Array User's Guide.

There's nothing in ANY Sun official doc released before 1997 that even
indicates the software *is* from VERITAS, with the exception of
copyright notices.

Note that, as of the new 2.4 release, the product is called Sun
Enterprise Volume Manager.  And, since Sun *does* sell it for full
function as well as bundling it with SSA's, the Sun doc does identify
the two modes more clearly.

> All in all, I like the hardware and was pleased with having the option of
> SDS or VxVM.  I honestly think that SDS is better than VxVM in a few
> areas.  

Obviously, we're interested in hearing these.  I can think of a couple
of legit
ones we're addressing: the ability to do optimized mirror resync at
times other
than crash recovery, and a cleaner Motif style-guide interface on the
GUI.  I
can think of others that are simple matters of UNIX-weenie preference,
such as
the building of objects partition-by-partition.  (Yuck.  There are much
better
ways to get the storage you wish, but it's not yet reflected in the GUI
-- see
the vxassist man page.)  And there are others that are
misunderstandings,
such as the notion that VxVM has no command line interface (hah -- I
worked with it before it even had a GUI at all), or that striped or RAID
volumes
cannot be grown (they can be, but not in the performance-broken method
where you tack a single disk on to the end of a six-way stripe -- you
don't get
a seven-way stripe, you get an unpredictable data-container; VxVM 3 will
in fact allow you to turn it into a seven-way stripe on-line).