Fibre Channel, HBAs, iSCSI, general IT knowledge?

Question

I am looking between two options, a pair of Emulex LPe1150-E cards or a pair of Dell XR997 cards. What I'm looking to do:

1. I have a RAID6 array with an NTFS volume on an Areca card.
2. I have my i5-2500k computer in my room.
3. My files I want far away (~30m wire path) in a rack case.
4. I won't settle for 1 gigabit speeds, nor do I want to mix traffic on my network, so I want a dedicated link.
5. One huge single volume showing up as a drive in Windows 7 x64 Ultimate.
6. Server will be some Linux distro. It will be an i7-970.

Would the Dell NIC with iSCSI be really too taxing on CPU cycles? This seems like the easiest route, as far as setting it up, and I know it will give me my file, but maybe really taxing on the hardware. I am really clueless about the alternate route, with Fibre Channel. Can that accomplish what I want? I don't get where people get their knowledge. Is it handed down through the IT generations like secret society-type stuff? I only ask because I can't seem to find any information on this. I have no problems understanding hardware, it's just the software side of things that menace my brain. I am racked because the cost of both is pretty equal, but I can't get into adventurism in seeing if one thing works, but then it doesn't. I don't pull much of an income, so I can't just go buying hardware left and right to play around with. I need a solution that I know will work.

Answer 1

If the NIC has ToE (TCP Offload Engine), it greatly reduces the amount of processing power required by the CPU. I would say that at anything > 1Gbps speed it is almost mandatory.

The difference between Fibre Channel and iSCSI is that iSCSI runs over IP, which is a lossy protocol (i.e. packets are not guaranteed to arrive in the correct order, or even at all), where as FC is almost the exact opposite.

Personally, I would go the iSCSI route. It's more bang for your buck, and at the end of the day you have a 10Gbps network. FC cannot be used for TCP/IP communications, whereas 10GbE can. Also, you can then just use the Windows iSCSI initator to make the volume show up on your other PC.

FC is rarely seen outside of large datacenters. But it's important to note that just because you're using 10GbE, doesn't mean you can't use fibre. You can (and may very well want to, if it's over 30 meters) use Fiber Optic cables to run your network between locations. That XR997 is a copper (CAT6 with RJ45) card though, so you would need to find two 10GbE fibre cards in order to go that path.

As for where do we get this info from? You're right, there's no real repository on where to learn this stuff, and yes, a lot of it is handed down when there's a need for it. Often by people asking questions just like yours. Or, if you're a business, you would go to Dell/HP/EMC/etc, explain your situation, and then they would hold your hand through the decision making process.

Answer 2

Generally most people learn about such stuff at work or through certifications - not through secret handshakes.

I'll start off with 10 gig-e. Most decent network cards (that is to say anything better than consumer level cards) have their own internal processor (the dells seem to have one that is powerful enough to need its own fan), and are unlikely to trouble the main processor excessively. The XR997s seem to use the regular 8p8 connectors, but you need to use cat 6a, not cat 5 cable. There's a lot of variability in 10 gig-e cabling types, which is probably why you're confused.

I'd note other than needing better grade cabling, this is identical to how you'd work with a standard 10/100/1000 network, and should be far simpler. You'd simply need to install drivers, set static ips on either end, and you're cooking with gas.

I don't begin to understand fiber channel - you can use it point to point it seems, however

As for the software side of things, you'll need the server set up as a iscsi target - on linux tgtadm seems to be the thing to use and windows 7 has its own iscsi initator