topic Re: LUN management on XP512 in Disk Enclosures

LUN management on XP512

cart — Tue, 02 Apr 2002 13:59:05 GMT

Hi,
Can anyone tell me on a XP512, what is the minimum size of a LUN? Can I create multiple LUN on a single array group?
How many LUN can I create on a XP512?

Thx,
Sundance

Re: LUN management on XP512

harry d brown jr — Tue, 02 Apr 2002 18:39:42 GMT

Can anyone tell me on a XP512, what is the minimum size of a LUN? *** couldn't find much, so I'd guess 2GB (but probably smaller).

Can I create multiple LUN on a single array group? YES

How many LUN can I create on a XP512? 8192

http://www.hp.com/cposupport/manual_set/lpg28558.pdf

live free or die
harry

Re: LUN management on XP512

cart — Wed, 03 Apr 2002 07:45:20 GMT

Is the LUN size only related to the open emulation?

I've read that there is a maximum of 256 LUNs per port. Is a port a bundle of 8 connector? Does that mean that you need to have the XP512 full with all the 32 port to be able to have 8192 LUN?

Thanks,
S

Re: LUN management on XP512

Insu Kim — Wed, 03 Apr 2002 13:58:28 GMT

>what is the minimum size of a LUN?
With Volume Size Configuration (VSC), you can create smaller LDEVs from standard Open-3, Open-8, Open-9 volumes.
The standard logical (non-VSC) logical devices are called "Normal Volumes" and devices create via VSC are called "Custom Volume".
Custom Volumes must be between 35MB and the maximum size of a single device -2.3GB for Open-3 devices and 7.0GB for Open-8 and Open-9 devices.

>Can I create multiple LUN on a single array group?
Yes.

> How many LUN can I create on a XP512?
The maximum of 4096 LDEVs for XP512.
The maximum of 1025 LDEVs for XP256.

Hope this helps,

Re: LUN management on XP512

Insu Kim — Wed, 03 Apr 2002 14:09:02 GMT

>I've read that there is a maximum of 256 LUNs per port.

The maximum of 256 LDEVs per Control Unit(CU) and there're one to 16 control units possible for XP512.
That's why 4096 LDEVs (256 * 16) can be created for XP512.
CU is a set of structures to manage LDEVs.

Hope this helps,

Re: LUN management on XP512

Roger Baptiste — Wed, 03 Apr 2002 14:15:55 GMT

hi,

If you are using standard OPEN emulation modes, then OPEN-K = 1.88Gb is the smallest. If you use customised emulation, you can create smaller LUNS. But, please note that it is preferable to create reasonable sized luns, since there is a limit to the LUNS seen by a fibre port (256 Luns) and there is also a maximum number of LUNS for XP512 (4096) limitation. Another reason is, it makes life easier while configuring VGs/LVs at the system end.

Regarding your other question, yes a RAID group gets split into different LUNS , its size depending on the emulation mode.

HTH
raj