XP Lun Limitations

[James Hicks]

What is the LUN limitation on the XP256 and XP512?

[Mark van Silfhout · Accepted solution]

The "limitation" for XP256 is 120 LUNS per Fibre port, for XP512 it's 240 LUNS per fibre port.
These are not "hardcoded" limitations but are performance driven. Adding more luns than 120 (or 240) will slow down performance.

Regards,

Mark

[Dave Wherry]

Mark's answer is correct for each FC interface. That's not the total for the entire frame though. Unfortunately I can't find the numbers right now.
I think the total LUN number for a 256 is a little over 1,000. You can have 16 FC interfaces times 120 LUN's per interface. That's 1,920. I think that is too high though. I just can't find my old documents.
I think the 512 can have up to 32 FC interfaces and 256 more disk so I expect the LUN number to be much higher. I just can't find it on the HP web site. They always make it a treasure hunt to find specs.

[Michael Lampi]

XP512 has a LUN limit of 4096.

[Mark van Silfhout]

You are almost right, the maximum numbers of LDEV's(!)for 256 is 1024 and for a 512 it's 4096 (with the current microcodes...).
However an ldev can be configured to multiple ports, so in theory you can have 32 ports * 4096 ldev's= 131.072 luns.