iSCSI Is The Future
Storage arrays are no longer magic and mystery. As Howard Marks explains in detail it isn’t very difficult to build multi-terabyte iSCSI arrays out of standard servers, adapters and software. And do it for less than $2/GB using high performance drives, less than a quarter of the cost of purpose-built iSCSI arrays. Extrapolating from Howard’s numbers, it looks like open source software and lower-performance higher-capacity drives could take that number to under $1/GB.
Room With A View
These aren’t bare bones implementations. Features such as RAID, IPsec, snapshots, multi-path I/O, volume and capacity expansion, and hot spares, are all available depending on the software. Howard covers both Windows and Linux software options. To compare the homebrew array to storebought, check out this review.
SMBs Step Right Up
Who should use iSCSI? If you haven’t already invested in Fibre Channel – and a surprising percentage of even large firms haven’t – don’t start! FC is costly in equipment and management for very little benefit. The major benefit is lower latency than iSCSI. Since FC isn’t a real network – note the Channel in the name – it doesn’t have the overhead of IP. For latency sensitive apps, mostly databases, stay with direct attached storage, which is even faster and cheaper. For everything else, iSCSI will be fine and a lot cheaper.
What Does It All Mean?
Which brings me to the point of this post: the place to start open storage is with arrays, not management. I’ll enlarge on this point later this week. Stay tuned.