Between lots of other activities this weekend, I fiddled around with my three new 1.5TB drives. It’s been years since I’ve felt like I took some sort of Apocalypse Now trip up the technological congo – but adventures in installing these drives has made me feel close again. What awful adventures getting some wild combination of things working in tech-land have you had?
- Getting more than 640k recognized in DOS on an IBM XT via a memory expander card (I had a 512k ram drive!)
- Getting an 8-bit IBM XT to boot from a very specific Seagate ST351A/X IDE drive (the only IDE drive ever that could run on an XT)
- Getting over 4gb of memory recognized (not hard -unless your motherboard has a bios bug that freezes the system up with four 1gb DDR2 sticks install -a bug I found and reported to Intel’s support guys…)
- Getting windows media player to stop f*** waking my system randomly in the night to update the program guide.
But anyway, TerabyteLand wasn’t quite as bad as those – but installing these drives helped me relive those days a bit. Long story short – don’t expect to boot from a volume over 2TB. Now, I have hardware RAID on my motherboard with ample SATA ports (six hot-swappable) and hardware support for RAID 0, 1, 5, and 0+1. My hope was to put all three drives in a RAID 5 setup for redundancy and read performance. I could successfully create the 3.0TB RAID 5 set, but it was reported as not bootable by an ICH9 and ICH10 RAID controller. After trying 2 other motherboards and digging around on forums, turns out due to current bios limitations.
MBR BIOS limitation to 2TB
Current BIOS uses MBR (master boot record) for drive support – and MBR only supports drives or partitions up to 2TB. However, the new EFI (extensable firmware interface) specification is a BIOS replacement that removes this limitation by allowing the new GPT (GUID Partitioning Table) format that supports up to 18 exobyte drives/partitions. So, in order to boot from a drive larger than 2TB, you need to have a motherboard that runs EFI (currently: Apple, Itanium, and HP-UX boards), and drives formatted with GPT. So at the moment, that means not much love for Windows world. You can create GPT partitions in Vista SP1 – but just not boot from them.
So, that leaves only two options: run my OS from one of my existing 750GB drives and then have the remaining 3.0TB in a second set as RAID 5, or put two drives in RAID 1 for the OS (mirroring for fault tolerance and read speed) and leave the second drive alone for DVR storage. I went option #2 – but I hate the fact I can’t just have one big bucket of bits. I HATE secondary drives that exist simply because of these stupid limitation. At least I’m not alone.
Still, even doing this was painful. Vista had trouble recognizing the drives when I first plugged them in. You had to format them with AHCI first, then switch the bios over to RAID and set up the volume – then vista could install to them. Weird.
Any of you set up a large bootable volume like this in Linux?