topic Re: Simple FIber Channel Question.... in Disk Enclosures

Simple FIber Channel Question....

Dave Onex — Tue, 17 Nov 2009 21:32:30 GMT

Hi Folks;

I was looking at used disk arrays and saw a EVA M5214.

It's a fiber channel array and I've never used fiber channel (I have zero knowledge or experience about it).

I found a Fiber Channel Bus Adapter kit for my server and so my question is, what's all required to use a fiber channel array?

Do you just need a fiber channel adapter installed on the server or is there more to it?

Thanks!
Marvin

Re: Simple FIber Channel Question....

Torsten. — Tue, 17 Nov 2009 21:42:48 GMT

Hi Marvin,

this is a famous name in computer world ;-)

The M5214 is just a disk container (enclosure), a part of an EVA, but not an EVA.

You need the array controllers, this is the EVA.

Re: Simple FIber Channel Question....

Dave Onex — Tue, 17 Nov 2009 21:53:35 GMT

Hi Torsten;

Thanks for the reply!

Let's keep it simple (because I have no understanding of Fiber Channel). I also don't know what an EVA is :-0

With SCSI you need an external array, cables and a controller card. With that in hand, you're set to go.

Assuming I had the FC array with disks, and the Fiber Channel Bus Adapter kit for my server, what's missing?

Does the server's FC adapter connect directly into the back of the disk array?

Sorry if the questions are dumb :-)

Re: Simple FIber Channel Question....

Torsten. — Tue, 17 Nov 2009 22:01:18 GMT

I don't know what "I know nothing about FC" means.

Let's compare like this:

With pure SCSI, you need a RAID controller and some disks to create and manage logical drives (RAID's).

With EVA is the same, you need array controllers and disks.

The M5214 is just disks, no RAID capabilities.

You need the "controller card" ...

Re: Simple FIber Channel Question....

Dave Onex — Tue, 17 Nov 2009 22:03:44 GMT

OK, how about this;

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290368597285&ssPageName=STRK:MEWAX:IT

plus this;

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200401389250&ssPageName=STRK:MEWAX:IT

What would I be missing to make it work?

Re: Simple FIber Channel Question....

Torsten. — Tue, 17 Nov 2009 22:09:06 GMT

Just parts of a body, without head and brain. Kind of useless.

Some basic information:

http://h18006.www1.hp.com/products/quickspecs/12408_na/12408_na.html

Re: Simple FIber Channel Question....

Torsten. — Tue, 17 Nov 2009 22:16:52 GMT

Just to give you an example:

http://cgi.ebay.com/AD525B-HSV200-Controller-Pair-EVA4000_W0QQitemZ160326392476QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2554329a9c

You see from top 2 servers, the controller pair and 2 disk enclosures.

You need the controller pair, you currently have the disks only.

Re: Simple FIber Channel Question....

Dave Onex — Tue, 17 Nov 2009 23:06:01 GMT

Aha!

I knew there had to be a reason the disk array was pretty cheap.

Are the controller pairs roughly equivalent to RAID controllers?

Re: Simple FIber Channel Question....

Serviceguard for Linux — Wed, 18 Nov 2009 01:08:21 GMT

Also, for the basics of something like Fibre Channel, it is always handy to use wikipedia http://en.wikipedia.org/wiki/Fibre_channel .

You can use Fibre Channel in a way analogous to SCSI. Just like SCSI, some "boxes" you can connect to are "dumb" JBODS (just a bunch of disk) where the OS sees every disk. Also, you can connect to a storage array (e.g.EVA 6400 http://h10010.www1.hp.com/wwpc/us/en/en/WF05a/12169-304616-304648-304648-304648-3900918.html ). These arrays have intelligence that implement various forms of RAID and partition up storage into any size LUN that is useful to you (and sometimes many other functions).

Also, just like SCSI, there are sometimes components that are "add-ons". I think the other responder pointed out that the product you found was of that type.

Re: Simple FIber Channel Question....

Dave Onex — Wed, 18 Nov 2009 02:04:03 GMT

Thanks guys :-)

What caught my eye was that the disk array (and disks too) seem to be quite cheap if they are Fiber Channel. This caused me to wonder how much (if any) I could save by going that route rather then SCSI.

All I was after was a 14 bay array with a divided backplane so I could hook one machine up to one side and another to another (2x7 disk arrays).

I thought that perhaps the Fiber Channel array could be made to do something similar and I was hoping that all I needed was a FC host adapter in the server. Clearly, that's not the case given that the controllers mentioned seem to be around 4K used.

In that case I'm better off with picking up a 4 channel RAID card, a split backplane SCSI disk array and some cables.

Thanks for taking the time to answer the questions and for setting me on the right track!