3PAR Users Group

minimum disks requirement for capacity expansion
Page 1 of 1

Author:  bervon [ Wed Dec 06, 2017 10:24 am ]
Post subject:  minimum disks requirement for capacity expansion


We have a small StoreServe 8200, single enclosure with 12 SSD's and need to upgrade capacity.
The question that we have:
How many disks are needed at minimum ?
is it 2 or 4 ?

Can we add the disks ourselves once purchased ?

thanks for your reply

Author:  MammaGutt [ Wed Dec 06, 2017 11:10 am ]
Post subject:  Re: minimum disks requirement for capacity expansion

2 is minimum, but recommended minimum depends on CPG set size.

Some countries allow you install yourself, others don't. If you are allowed, remember to check SPOCK for minimum firmware required for the addon as the exact SSD model may have changed since you got the system. If you install them without the correct firmware they will not admit, you just remove the drives after install they may not be accepted when re-admitted, so read first, check second and install third if you do it yourself.

Author:  bervon [ Thu Dec 07, 2017 4:47 am ]
Post subject:  Re: minimum disks requirement for capacity expansion

Thanks for responding

When I look at the quickspecs for the 8200, I come across this :

https://www.hpe.com/h20195/v2/GetDocume ... =c04607918

“Minimum upgrade quantity is 4 drives per node pair or 2 drives per enclosure, whichever is larger.”

When I use NinjaStars to get an indication of usable capacity after adding disks, I don't get warned when I select 2 disks to add to the system. This is why I get in doubt of what the minimum would be.

So, Can I trust NinjaStars when it doesn't complain when adding 2 disks instead of 4 ?
Or do I need to follow the quickspecs ?

By the way, we use RAID5 (5+1)

Author:  JohnMH [ Thu Dec 07, 2017 3:53 pm ]
Post subject:  Re: minimum disks requirement for capacity expansion

forgetting cage HA then it's two minimum per node pair or two minimum per enclosure if you are adding across multiple enclosures i.e. you always need an even number of drives per enclosure, but not necessarily the same number per enclosure.

Also if you don't add in set size x nodes e.g. 5+1 x 2 nodes = 12 disks (assuming a balanced config). Then you'll need the tunesys to complete before you can access all of the new space.

Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group