Max disk devices HP-UX

[Darren Chambers_1]

Hello all, At present I've been tasked with connecting multiple storage arrays to multiple hosts. The storage arrays are already in use & so are already advertising disks. One of our hosts can see 980+ devices. My worry is that there is a maximum number of devices HP-UX can see. If this is exceeded, what happens ? Box crash ? Invisible disks ? Please Help

[steven Burgess_2]

Hi Darren

http://support4.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000024128251

HTH

Steve

[Darren Chambers_1]

Cheers Steve, that helped but we use HP-UX 11, soon moving to 11i across the board. Do you know how many disks these OS's are able to deal with ??

[steven Burgess_2]

Hmmm

Can't find anything for 11 or 11i , will continue looking and let you know if I find anything

Steve

[John Poff]

Hi Darren,

I have run into an issue in the past with Fibre Channel cards connecting to an EMC disk array. There is (or was) a limit of 128 LUNs that could be seen from a single FC controller card.

JP

[Dietmar Konermann]

There are a number of factors that lead to LUN count maximums. The device itself can have limitations, the adapter/driver pair can have limitations and the Server itself can have limitations.

The HP-UX Operating System supports 1024 active hardware paths concurrently (i.e. LUNs that are opened). The non-active hardware paths are not counted (i.e. alternate paths are not counted regardless of the number of alternate paths).

Regards...
Dietmar.

[Ashwani Kashyap]

You can have 2400 active Luns under 11.0 and 4096 active luns under 11i .

Open/visible ( PV Links ) 4800 under 11.0 and 8192 under 11i

512 LUNS/HBA ( NON HA ) under 11.0 and 512 LUNS/HBA ( NON HA ) under 11i.

320 LUNS/HBA (HA) under 11.0 and 512 LUNS/HBA (HA) under 11i.

[Dietmar Konermann]

Hi!

Sorry, my fault. The text I quoted from unfortunately contained some contradictions.

The above numbers are indeed correct. The official white paper is:

http://www.docs.hp.com/hpux/onlinedocs/netcom/maxlun-whitepaper-v1.0.pdf

Regards...
Dietmar.