HP P400/P800 >2TB Drive Support

This is most likely the DL320S model (storage server) that you are mentioning. The quickspec below listes 750GB as the largest size with the P400 controller/256 cache.

http://h18000.www1.hp.com/products/quickspecs/12654_div/12654_div.PDF

The only reason the spec says 750GB was because that was the largest HP disk shipping at the time they made the literature.

that makes sense.  I dislike the fact that they don't update the quickspec which leaves you searching for comparible drives...

I know that it accepts 2TB drives and if needed I've got a spare P800.

There shouldn't be any difference between the P800 and P400 in this since they both have a LSI SAS 1078 ROC (with HP's RAID stack rather than LSIs), the P800 just* has a PMC-Sierra expander chip added to give it more ports.
The ROC supports disks above 2TB AFAIK but I'm not sure HP's stack does, maybe there will be a firmware update in the future if it doesn't run with disks over 2 TiB.

* Before anyone bites my head off this is a simplification, there are other differences but they aren't relevant to whether they support 64bit LBA on the disk side.

To cross the 2TB barrier, you need firmware/BIOS upgrades as the drives require yet another new translation to be handlesd properly.  Nothing on the HP support site leads me to belive they have issued such an update: http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareIndex.jsp?lang=en&cc=us&prodNameId=1157689&prodTypeId=329290&prodSeriesId=1157687&swLang=8&taskId=135&swEnvOID=54

I think you'll either get the drive not recognized or only see 2TB :(

Ile get a couple of drives and try it out.

The problem is NEVER going to be with the disk drives.  This can be proven rather easily with a thought experiment.   Why would anybody manufacture a disk drive that was incapable of accessing 100% of the data on it.

@dlethe..accessing 100% of data..who needs it?  Just like marketing 1000 bytes instead of 1024..I keep wondering where my GBs go now I know

<-tounge in cheek

giga = 10^9, you should be asking why you're getting a gibibyte of RAM when you only asked for a gigabyte.

http://en.wikipedia.org/wiki/SI_prefix

<tongue also in cheek> ;)

Was thinking of SAN Vendors and difference between market size/raw size/actual size..YMMV

Already said what ROC it uses. Re-jigging the metadata isn't really a problem as HP only offer backwards compatibility so a new controller just has to be able to read new as well as old metadata. They have added extra stuff to the RIS before, I would expect them to do the same in the future - you can see that by comparing ADU reports on old and newer controllers.

Agreed, but this is so much work, for a SAS-1 product, I just don't see the ROI now with SAS-2 in GA.

Yup, you're right. Probably introduce it to the next generation which will help them sell you a whole new set of servers too.

.. and SAS switches too!

HP have had SAS switches from 2009 for their blade enclosures, they're only 3Gb but that's 6Gb from each switch to the HBAs in the blade servers as 2 lanes, and 12Gb to the disk unit with all 4 lanes; doubled again as two paths. HBA's a bit expensive as it's a RAID controller running in non-RAID mode.

so far the info ive found points towards the P400 not supporting 3TB+ drives, found a page saying that the LSISAS1078 chip does not support 32bit LBA, not sure what the new P410/P810 cards use though

http://communities.intel.com/message/123688

GRRRRR, annoying

P410 runs a PMC-Sierra ROC, not sure which one though. Again it's got HP's raid stack on it so disks can be moved from one to the other while preserving the data.

not much info on PMC-Sierra ROC stuff, but suspect as its new HP cant be so dim to leave off 2TB+ support but as you said they use a unified software stack so that needs to be up to scratch too, how annoying i may have to just get a LSI card which i know supports 3TB drives

In the end I went with the LSI 9260-4i card as it supports 3TB drives, its a cludge as the HP DL320s its put into means that the controller does not correctly know the backplane layout, its all skewed but seems to work fine in the OS.

While it was worked out by one answer that the P400/800 does not support 2TB+ drives there was no indication to when or if the P410 also has the same problem.

Hot off the press:  HP just released new firmware to support disks greater than 2TB.

http://h18000.www1.hp.com/products/quickspecs/13021_div/13021_div.pdf

NOTE: To support HP hard drives exceeding 2.2 TB, HP Smart Array
Firmware version 5.0 or later is required for the following controllers:
HP Smart Array P212 Controller
HP Smart Array P410 Controller
HP Smart Array P411 Controller
HP Smart Array P711m Controller
HP Smart Array P812 Controller
To use hard drives exceeding 2.2 TB, you must create a boot volume using
offline ACU version 8.75 or later. HP Smart Array controllers do not support
boot volumes exceeding 2.2 TB.

grrr bummer, now im in a pickle if i should rebuild the server with a proper HP card over the LSI i put in

I'd stick to the LSI now you've got it working since it's designed for generic disks, HP's controllers work with generic ones but some parameters are tweaked in the firmware of the HP disks to better match the controller.