topic Luns Limit in Operating System - HP-UX

Luns Limit

Filosofo — Fri, 03 Nov 2006 04:18:57 GMT

Hi,
I have an rp8420 with 2 HP Tachyon XL2 connected to a symmetrix storage.
I have received this error from ELM messages:

"The system has reached its maximum device addressable limit "

My question is, How many Luns can I attach to my Host?

Thanks for help

By

Re: Luns Limit

Peter Godron — Fri, 03 Nov 2006 04:23:19 GMT

Hi,
how many LUNs have you currently got. That would be the maximum ;-)

"
Severity: Critical
Description: The system has reached its maximum device addressable limit

Cause: The total LUNs discovered by the host bus adapter through all the fibre channel devices is beyond the system addressable limit. This can happen if there is a large number of LUNs configured (either in a single fibre channel device or in multiple devices).

Action: Configure fewer number of (larger) LUNs.
"

Re: Luns Limit

Alzhy — Fri, 03 Nov 2006 10:56:22 GMT

It will depend possibly on the per HBA LUN presentation limit which I think is 1024 (un sure though).

But there is a limit obviously.

How many LUNS so far have you presented to each XL2 ? And what kind of SAN Storage array are you using?

Re: Luns Limit

Marvin Strong — Fri, 03 Nov 2006 12:05:16 GMT

Well from my knowledge

c= 0 - 255
t= 0 - 15
d= 0 - 7

I'll let you do the math on how many that is.

I thought I remember reading somewhere the recommended limit was 4096. But I can't seem to find anything supporting that info right now.

Re: Luns Limit

James R. Ferguson — Fri, 03 Nov 2006 12:10:39 GMT

Hi:

Perhaps this document will help you:

http://docs.hp.com/en/7154/Max_LUN_whitepaper_v11.23.pdf

Despite the URL, the document addresses HP-UX 11v1 and 11v2.

Regards!

...JRF...