HPE MSA 2060 MSA-DP+ advise

[dmontalan]

Hello everyone,

I have a question about the MSA 2060 and the best configuration option for my case.

I have 24 HDDs of 900 Gb.
I want to use MSA-DP+ on a single pool/controller

What is the best option in terms of fault tolerance and performance?

- 1 group of 24 discs in MSA-DP+?
- 2 groups of 12 discs in MSA-DP+?

Also, in both cases, is the fault tolerance really two disks?

Thank you very much to those who can advise me.

[JonPaul]

@dmontalan 
The MSA-DP+ disk-group RAID level is designed to be a single disk-group per tier (Archive, Standard and Performance).  You can only make 4x MSA-DP+ disk-groups on a pool.
Here are some good resources 
MSA Best Practices:  https://www.hpe.com/psnow/doc/a00105260enw
MSA Virtual Storage Tech reference:  https://www.hpe.com/psnow/doc/a00103247enw
In a nutshell MSA-DP+ is a 10 drive RAID 6 (Dual Parity) but it can make use of more drives by selecting different drives for 'stripe zones'.  There is also 2 drives of spare capacity spread throughout the disk-group by default, a little on each drive.  More spare capacity can be chosen but must be set during creation or before expansion of the disk-group.  See documentation about spare capacity recommendations.
The fault tolerance is 2 drives at a single time, more drives can be lost when the rebuilds complete.  In a 12 drive MSA-DP+ you can lose 4 drives over time without losing data (2 drives worth of SPARE capacity and the 2 drives of parity for RAID 6).  In larger disk-groups you can lose more disks depending on the capacity of the disk-group used.  

[Mulesh_Vedant]

Hi

If I make a single RAID Group from 12 disks (and configure MSA-DP+), can I carve out multiple LUNs 

and then mount these LUNs on both the controllers? As I understand, most storage allow this.

Thanks

Mulesh

[JonPaul]

@Mulesh_Vedant 
Short Answer: Yes
Longer answer:  The MSA-DP+ disk-group will be placed into a Pool (A or B).  From the Pool the volumes are carved out.  The volumes are then mapped to LUNs and presented to the hosts,  all LUNs should be mapped to BOTH controllers and all hosts should have at least 1 Path to the LUN on controller A and 1 Path to the LUN on Controller B.  
If the host multipath is setup correctly then there will be optimized and non-optimized paths to the LUN and the host will use all the optimized paths before using any of the non-optimized paths (This is ALUA, asynchronous logical unit access).