Re: Port Multipliers

[Richard Scobie <richard@sauce.co.nz>]

Drew wrote:
>>If you're looking at port multipliers, you need to find PCI-Express
>>modules if you want them to be fast. The PCI ones are gonna be very
>>slow when you have more than 2 disks per card.
> 
> 
> The existing server we're planning to re-purpose for this is an IBM
> xSeries with two free PCI-X/100 slots and dual PCIe/x4 slots.

Your best bet might be to use one of these HBA's:
 
http://www.lsi.com/storage_home/products_home/host_bus_adapters/sas_hbas/lsisas3801e/index.html

although you would need to check whether it functions OK in an x4 slot - 
obviously the maximum performance will not be reached, but if you are 
only using one output you should be OK.

This would then be connected to an enclosure like this:

http://www.aicipc.com/ProductDetail.aspx?ref=XJ1000%20series%20-%203U%2016-bay

which contains a port expander to all the drives.

I have been running 2 similar setups (although using the LSISAS3442E-R 
version of the HBA - around $US230 in an x8 slot), for over a year 
without any trouble, with the drives configured as an md RAID6.

The HBA's can have an alternate firmware loaded which removes the 
onboard hardware RAID0,1 functionality.

Regards,

Richard