@zubbs1: SATA port multipliers will work fine under FreeNAS and other BSD/Linux operating systems. Not all controllers support port multipliers; but your onboard chipset SATA controller should support it. Note that it is not the best way to connect many disks. But remember you can combine ports from your chipset with an addon controller like IBM M1015 (flashed to IT). This is often done by ZFS users. Why RAID1 and not RAID-Z? Have you read up on ZFS? Could you tell us a little bit about what you're hoping to accomplish?
Basic specs of a nas box I was thinking to build:
Motherboard - ASUS H87I-PLUS LGA 1150 Intel H87
Case - NZXT Source 220 CA-SO220-01 Black Steel
Power Supply - Thermaltake TR2 W0070 430W ATX12V v2.3 Power Supply
CPU -Intel Celeron G1820 Haswell Dual-Core 2.7GHz LGA 1150 54W Desktop Processor Intel HD Graphics BX80646G1820
Memory -Mushkin Enhanced 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1066 (PC3 8500) Dual Channel Kit Desktop Memory Model 996573
Operating System Drive - Not sure specifically, SSD I presume? Recommendations?
Hard drives - WD red not sure yet on total number or indvidual size per drive.
The motherboard has 6 sata ports leaving 5 for the hard disk pool. I just wanted to make sure that was enough to get my usable storage space up to 10TB. If it can, then I have no need at this time for any port multiplying.
I admit my understanding of raid and ZFS is limited. My basic goal is to get all my media on one disk pool that has some level of redundancy against loss.
My media collection is not a 10/10 on a 'cannot lose' scale, more like a 5 or 6. My most critical data i have saved over several hard drives, flash drives and dvds, so I'm not worried about absolutely no loss. With that in mind, I also don't want to spend a fortune in hard drives for half the actual storage.
Hopefully that gives you a better idea of my needs. I also am not in a hurry to build this, so it can be a work in progress and be piece meal as long as I have a framework to follow.