topic Re: eva vertical disk group in Disk Enclosures

eva vertical disk group

ilayy — Wed, 17 Nov 2010 00:01:53 GMT

hi all
i have read that to have better performance we have to add disks to disk group vertically but i am confused about what does it mean exactly for example if we have eva 4000 2c 2d
if in the first enclosure i add the first 2 disks to right and on the second enclosure i add 2 disks to the left is that considered as vertical or it should be in the same bay?

Re: eva vertical disk group

Steven Clementi — Wed, 17 Nov 2010 00:41:57 GMT

Yes.

Vertical simply means to spread out your disks among all shelves.

The bays don't really matter, but for future expansion and/or usage of difference size disks... it may be a good idea to keep your same sized disks together.. for better visual management.

Steven

Re: eva vertical disk group

Sivaramakrishna_1 — Wed, 17 Nov 2010 02:13:31 GMT

The Idea of having Vertical DG is good way to split the RSS vertically across the enclosures. It will be more helpful for the case of mimimum 8 or more enclousures.

In such case each Disk Enclousure is having only 1 RSS member of that RSS.

Here is the example, suppose if you have EVA6000/8000 with 8 Enclosures with Full populated (112 Disks). If you initialize there will be total 14 RSS groups will be created. So each RSS group will have only one member on the Enclosure. In this case even Enclsoure failure also doesn't effect the produciton due to the virutualization feature.

This will not be in a same manner all the way and subjected to change when if any disk failure. RSS split and merge operation change this behaviour)

Re: eva vertical disk group

ilayy — Wed, 17 Nov 2010 07:40:55 GMT

hi,
than for your fast reply. my questiom just was does the bay number has meaning in vertilca distribution?
so the disks should be in the same line (bays number) to be in vertical configuration or no? for example 2c 8d
if in the first disk group i have 8 disks(each disk is in a seperate enclosure) the 8 disks should be all in the same bay number to be in vertical configuration or even if it is not they are in vertical configuration?

Re: eva vertical disk group

Steven Clementi — Wed, 17 Nov 2010 13:51:09 GMT

"... the 8 disks should be all in the same bay number to be in vertical configuration or even if it is not they are in vertical configuration?"

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Vertical simply means to spread out your disks among all shelves.

**The bays don't really matter**, but for future expansion and/or usage of difference size disks... it may be a good idea to keep your same sized disks together.. for **better visual management**.

As long as your disks are spread out as equally as possible among all of your disk shelves... it's vertical.

Steven