Ok, We are going to be virtualizing our entire system here over the next year and we obviously need a SAN. I engaged Dell (equalogic) and IBM (DS4700) to provide me with solutions. Now i have worked the vendors over for about 3 months and have them practically giving me the stuff.
both solutions meet the following needs
- 16TB of RAW space
- Primary box at main datacenter all 15K 450GB drives
- Second box across campus all SATA drives
- Both solutions provide snapshots/volume copy and replication.
The IBM solution is fiber and is obviously going to be faster on the network side. It has dual controllers that have 4 4GB ports each. So that's a total of 32GB's of controller thruput. Each server will have dual 4GB NICS. It also replicates to the remote box via direct fiber connections.
Now... the IBM solution doesn't have a nice interface. It sucks. It also doesn't provide any reporting or trending tools with the unit. It doesn't automatically auto tune itself (i.e. add spindles as needed) It requires knowledge of fiber channel san networks that i don't have any experience with. it does however allow me to add drives individually and of the SATA or FC flavor. The expansion bays are affordable as opposed to buying a full equalogic box.
On the other side..
The equalogic solution provides us with two controllers to the IBM one, and since it is failover only on their controllers, you get 4GB per box, so that's 8GB of total controller throughput. The servers all have 4 1GB ports for a total of 4GB per server. There is a significant difference in bandwidth in the two products. Now I keep hearing about MPIO and i'm no expert on it, but heard that even with MPIO the SAN can only talk to one nic port at a time. If that's true, then the bandwidth needle on the equalogic just went down. But they say MPIO allows you to use all the NICS to get 4GB per server if the box has 4 1GB NICS.
With all that being said. The IBM solution is only 10K more. I won't give out numbers but i can tell you that if you know how to work deals you can get fiber for almost the same cost as ISCSI, at least in the Entry/Mid range market. Anyways, this may seem like a no brainer but i just wanted to see what the experts think about my situation. Especially with 10GB NICS coming out. the equalogic is supposed to support that upgrade. I fear that i am losing a lot of administrative functionality and ease of use that in a small shop is important. I also can't afford to be wrong and end up with a product that will be 'IO'd out' if you know what i'm saying.
any help would be appreciated