[gpfsug-discuss] gpfs native raid

[Aaron Knister]

Thanks Everyone for your replies! (Quick disclaimer, these opinions are 
my own, and not those of my employer or NASA).

Not knowing what's coming at the NDA session, it seems to boil down to 
"it ain't gonna happen" because of:

- Perceived difficulty in supporting whatever creative hardware 
solutions customers may throw at it.

I understand the support concerns, but I naively thought that assuming 
the hardware meets a basic set of requirements (e.g. redundant sas 
paths, x type of drives) it would be fairly supportable with GNR. The 
DS3700 shelves are re-branded NetApp E-series shelves and pretty vanilla 
I thought.

- IBM would like to monetize the product and compete with the likes of 
DDN/Seagate

This is admittedly a little disappointing. GPFS as long as I've known it 
has been largely hardware vendor agnostic. To see even a slight shift 
towards hardware vendor lockin and certain features only being supported 
and available on IBM hardware is concerning. It's not like the software 
itself is free. Perhaps GNR could be a paid add-on license for non-IBM 
hardware? Just thinking out-loud.

The big things I was looking to GNR for are:

- end-to-end checksums
- implementing a software RAID layer on (in my case enterprise class) JBODs

I can find a way to do the second thing, but the former I cannot. 
Requiring IBM hardware to get end-to-end checksums is a huge red flag 
for me.  That's something Lustre will do today with ZFS on any hardware 
ZFS will run on (and for free, I might add). I would think GNR being 
openly available to customers would be important for GPFS to compete 
with Lustre. Furthermore, I had opened an RFE (#84523) a while back to 
implement checksumming of data for non-GNR environments. The RFE was 
declined because essentially it would be too hard and it already exists 
for GNR. Well, considering I don't have a GNR environment, and hardware 
vendor lock in is something many sites are not interested in, that's 
somewhat of a problem.

I really hope IBM reconsiders their stance on opening up GNR. The 
current direction, while somewhat understandable, leaves a really bad 
taste in my mouth and is one of the (very few, in my opinion) features 
Lustre has over GPFS.

-Aaron


On 9/1/16 9:59 AM, Marc A Kaplan wrote:
> I've been told that it is a big leap to go from supporting GSS and ESS
> to allowing and supporting native raid for customers who may throw
> together "any" combination of hardware they might choose.
>
> In particular the GNR "disk hospital" functions...
> https://www.ibm.com/support/knowledgecenter/SSFKCN_3.5.0/com.ibm.cluster.gpfs.v3r5.gpfs200.doc/bl1adv_introdiskhospital.htm
> will be tricky to support on umpteen different vendor boxes -- and keep
> in mind, those will be from IBM competitors!
>
> That said, ESS and GSS show that IBM has some good tech in this area and
> IBM has shown with the Spectrum Scale product (sans GNR) it can support
> just about any semi-reasonable hardware configuration and a good slew of
> OS versions and architectures... Heck I have a demo/test version of GPFS
> running on a 5 year old Thinkpad laptop.... And we have some GSSs in the
> lab... Not to mention Power hardware and mainframe System Z (think 360,
> 370, 290, Z)
>
>
>
>
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