HPE Storage Users Group

Dear All,
Hi

I have a HP 3 Par 7200 system with 2 nodes & 5 Cages :

1 cage that contains FC Drives
4 Cages with NL Drives(4*24)

When i want to create CPG with NL SAS Drives if i want to use Disk Filtering and for example selecting Disk ID 55 up to 65 NL SAS HDDs from 96 available Hards,this message appears :

[size=150]System does not have enough space[/size]
You can find this image in attachment.

And i can not continue to finish CPG creation but if i do not use Disk Filtering everything is OK.

Would you please help me to solve this problem?

BR,
Nima

What RAID config (type & set size) and availability (cage/mag) are you choosing? What are you hoping to accomplish by using disk filtering?

The system can't meet the requested availability level (raid/mag/cage) based on the filtered drives you have provided for creating the CPG. e.g for Raid 6 which is the default for Nearline disks you'll need a minimum of 12 disks and you have 11.

But as above why are you filtering drives, it's not really a good idea unless you have a good reason, so what is it you're looking to achieve ?

Dear Adam,
Hi

The Raid is (6) , And the set size is (6+2) and the availability is (Cage).
It is the request from customer.

Many Thanks for your help.

BR,
Nima

Dear John,
Hi

I changed the availability level to (Magazine) and i filtered 12 Drive,after that i could create CPG.
The only reason for doing this is the (Customer Request) and i know it is not a good idea.
Many thanks for your help....

BR,
Nima

Hi Nima.

I know the customers word is law in consulting, but i would advice you to educate them a bit in best practices for 3par, and i do not believe limiting IO to certain drives fall under that category

If they are Sane people, they will appreciate it, and wont run into issues due to a misconfigured array.

Sooner or later they will also run into space troubles... Some of their NL disks could reach their capacity and other not putting down global NL perf...

besides that, drive numbers are never fixed. if one NL drive fails and is replaced it will get a different number which will be outside of the filtered range, giving interesting issues when the system needs to grow a volume.

To make matters more interesting, if after that a FC drive gets replaced it might get the original NL drive number, mixing FC and NL in the same filter.

Personally i would never ever EVER use drive numbers for filtering.

_________________
The goal is to achieve the best results by following the clients wishes. If they want to have a house build upside down standing on its chimney, it's up to you to figure out how do it, while still making it usable.

You can filter on mag and cage too...

Dear,
Hi

Thanks for your comments & advices.
I told them your comments but it was very important for them to do this because they thought it was something wrong with the device:)

Thanks for taking this in to your consideration...

BR,
Nima