Simple SAN setup.

[Buddha Bart]

I'm having the hardest time finding simple info on SAN equipment, everything seems very geared toward high-end setups.

I'm interested in having 3 - 11 servers utilize the SAN. Storage space is a very minor issue. What i'd like most of all is to eleminate any major points of failure (though dual HBAs seems overkill to me) and be able to do somthing like give ServerA read/write to a partition while ServerB, ServerC, and ServerD have read-only to it.

What would I need? My guess is an HBA for each server, and some sort of storage array/device (well i guess 2). Would I then need a switch/hub like device?

bart

 

[spidey07]

Buddha,

A simple SAN works much like a simple LAN. Each interface (HBA) works like a NIC with its own MAC address (world wide name). The fault tolerant solutions are proprietary to each SAN enviroment.

For now it is best to stick with a single vendor solution as the bugs are being worked out.

For example we use McData fiber directors (oem'd for EMC) for the SAN connectivity and EMC power path software to handle the fault tolerance of dual HBAs attached to separate directors. This SAN in turn is connected two multiple EMC farms and about 36 tape drives for backup. We have to backup 40 TB overnight, and without a SAN it would be impossible.

Maybe if you give some more details I can help out? What are your primary goals in order of importance? What are must requirements and what are may specs?

-edit- there are some white papers for hitachi, EMC, HP/compaq, and dell on their respective sites.

 

[Buddha Bart]

Thanks Spidey,

I'm actually interested in it for two reasons.

1.) A class I'm in now has us making up a fictional company and their "network" (which to this teacher includes servers). I took the server piece of it, because I've done stuff like this before, but I'm interested in SAN because I don't know much about it, but it looks like it could really solve some problems. For this fictional setup I'm just gonna cover the obvious ones like dhcp, dns, www, email, directory, and file service. What I was hoping to do was create a setup where everything is in some way n+1 redundant (probably just failover for all of them), but this always makes keeping the two servers in sync a pain (see 2 below).
So does something like this make any sense? What would I buy for the SAN switches? What about the Storage devices? Is there any way built in to have the secondary storage device just be a mirror of the first. I was able to find some compaq/hp gear on their website that looks like the right stuff, only there's no prices, they just say to call (never a good sign).

2.) I'm also a student-worker for the IT department (web specifically) and recently I got to totaly redesign the webserver setup. One of the most annoying things about the new setup (besides the fact that as a student worker i wasn't alowed to have any access/control over it, and its totaly beyond the staff server admin who now has to deal with it) is keeping the multiple copes of the website (on the different webservers that traffic is load balanced across) in sync. I figured a SAN might be an easy way to have all three webservers read from the same copy (I tried NFS, but even with soft-mounts it wont fail-over without the webserver remounting the drive).

I went out and bought the little O'Reilly SAN & NAS book, but its more an overview of the technology than actual implimentations/management.

bart