XP12000 - Is there a need to populate Array Groups in the DKC?

[Alzhy]

Also, are the array groups only hooked up to ACP Pair 1?

[Peter Mattei · Accepted solution]

Well, technically there is no need to populate the DKC drives but the HP recommendation is to first populate the DKC drives and then the DKU R1 drives and so on.

Another remark: It is cheaper to start with the DKC drives for small configurations because you will not need a DKU frame for up to 128 (incl. spares).

Yes, the DKC drives are attached to ACP1.
Find attached an overview I drew. The ACP and their drives are colored in the same colors.

Cheers
Peter

[Alzhy]

Peter,

Thanks. the XP12000 stencils and templates from VisioCafe were also very helpful.

BTW.. if we're getting the 4 DKU's and 4 ACP's -- are there any Array Group Population rules that I should request from HP? Should I request population so all the array groups are distributed amongst the 4 DKU's and ACPs (which is our practice with our 9960 /XP512)?


Thanks.

[Vincent Fleming]

If evenly distributing the array groups among ACP pairs is your standard, there's no reason to stop doing that. I think it's a good idea, personally.

Good luck,

Vince

[Peter Mattei]

Yes, a symmetrical approach allows for best load distribution!
Symmetrically does not necessarily mean same disk slots but about the same number of array groups per ACP.
What are you running, Unix with LVM or others?
If Unix with LVM (i.e. VxVM) I you would spread the LUNs of each Volume Group across all four ACPs!

Enjoy your XP12000.
It is a great Array.

Peter

[Alzhy]

Thanks once more guys... Our exprience with a XP512 (a HDS9960 actually) is helping us tremendously. Our initial number of disks will probably fit in just the 2 DKU's but we've spec'd the whole 4 DKU's and 4 ACPs - I am recommending (if it is possible) that the DKC be unfilled at the moment (or simply resserve it later on for FATA drives -- if we ever come to that.. so our naming standard will only concern the 4 DKU's and ACP's.

We're planning to use both LVM and VxVM - but purely HP-UX 11.0/11i environments in the meantime.

Btw:

1) what's the maximum LUN count per CHiP port on the XP12000?
2) what "mode" supports DMP for VxVM? In the manuals - it does not evenmention DMP for Veritas.

Thanks.

[Peter Mattei]

Hi Nelson

1. A single XP12000 FC port can have 1024 LUNs.
2. Host mode for HP-UX is always 08 no matter if DMP is used or not.
3. You will most probably never see FATA drives in the XP! The concept to provide cheaper storage to the XP is â External Storage XPâ where you can connect various types and brands of storage external to the XP12000.
An external LUN will then be used as LDEV(s) in the XP and can be used as if they were internal to the XP!

The lowest cost can be achieved by attaching MSA1500 with SATA drives.

See the two attached slides for the concept.

Cheers
P