Recently, I was involved in discussions with a company that has spent over $80,000 purchasing 6 servers for file and print services, database and backup with almost 4.5 TB of internal storage.
The company didn't want to go to Fibre Channel (FC) Storage Area Network (SAN) because of the cost involved and complexity, which I can understand. But what I don't get is why companies continue to purchase internal storage when direct attached external storage is becoming cheaper everyday.
My rule of thumb is if you are purchasing 1.5 TB of total internal storage or going to have more than 500 GB per server on average, think again. External Storage may be a good option for you.
I also believe that this is a very sweet spot for iSCSI storage array manufacturers. Instead of trying to outgun FC storage and FC SAN or positioning as a cheaper "SAN" using iSCSI, focus on replacing internal storage and direct-attached external storage. This may be the opportunity iSCSI companies are overlooking.