Question about EVA systems

[nemanja.stosic]

Hi to all,
If I have an EVA system, 4 disk enclosures. All the disks are 147GB, in one disk group. If I present 10GB vdisk, to one host, how will EVA system pick up the place from which disk to take that? Is it going to take that place only from one disk, or from 2 or more? General question is, if the vdisk size is smaller that one physical disk, is it going to take tha place only from one disk?

Thanks

[Víctor Cespón · Accepted solution]

For performance reasons the EVA distibutes the vdisk space among all disks on the disk group.

Say you have 50 disks and you create a 100 GB vdisk in vRAID 1. The EVA will take 4 GB from each disk, writing each data segment on two disks.

[Uwe Zessin]

The virtualization is so fine-grained that that data of a virtual disk with 1 GigaByte (smallest possible size) can be distributed across all 240 disk drives (maximum number of disks possible on _large_ EVA systems).

[Brandon Madanjit]

EVA's are an amazing piece of Hardware. For instance, if I have an EVA with a disk group of 10 x 300GB drives, and I created a vdisk of 300GB, the EVA would distribute this vdisk over all 10 (300GB) disks. Approximately 30GB will be assigned to each disk, therefore distributing your vdisk accross every drive in the disk group resulting in a lower overhead and high tolerance against failure.

[nemanja.stosic]

Thanks, for quick answers. I have got one more question.
Are 300GB disks suported on EVA 5000 vcs4, we have upgraded our contrrolers to that they can work as active/active. And what is the max storadge supported by EVA 5000.

Thanks Nemanja

[Uwe Zessin]

The EVA5000 can 'map' 32 SoftWare / 35 HardWare TeraBytes. That capacity can exist in form of virtual disks, clones, containers and snapshots. So in some cases you CANNOT utilitze the whole 'raw' capacity.

Here is a customer advisory:
c00838520 - Advisory: HP StorageWorks Enterprise Virtual Array EVA3000 and EVA5000 Usable Capacity Limited to 35 TB

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c00838520&prodTypeId=12169&prodSeriesId=3664763

[Víctor Cespón]

List of supported disks by firmware version:

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c01114153&jumpid=reg_R1002_USEN

Also, on the VCS 4.100 release notes:

http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01608153/c01608153.pdf

So the maximum size per disk is 500 GB. And the maximum number of disks is 240.