[HH] AoE controller

[Tom Metro]

When I first heard about ATA over Ethernet[1] (AoE) my thought was that
this could be a really interesting technology if you could get low costs
adapters to stick on drives and then string an arbitrary number of
drives together via Ethernet.

Instead, the initial hardware products resembled typical multi-drive SAN
appliances.

I did eventually run across a product that worked the way I envisioned:
http://www.jwe.com.tw/product_04.htm

Sold as a "development kit" for $75 ($35 shipping). The board has one
SATA and one Ethernet port and implements AoE.

With the availability low-cost ARM-based SoC devices like the Raspberry
Pi I've been wondering if it would be practical to make a single drive
AoE adapter that hits the $30 to $50 price point, running open source
firmware. The one obvious missing thing from the readily available SoCs
are SATA ports, but I bet there are some consumer NAS SoCs that include
them.


While writing this I ran across:

LayerWalker Technology
http://www.layerwalker.com/products.html#LW6800_LW16800

which makes an SoC specifically for AoE, though some of the information
suggests it only has an IDE interface, suggesting it is a dated part.
Elsewhere they mention SATA support, but unclear if they are referring
to their SoC part or something else.


Developing the firmware for such a device won't be trivial, if you want
high performance and reliability. The easy approach would be to just run
Linux with one of the AoE servers[2,3,4], but that could incur a lot of
extra overhead and complexity. But it may be the only practical
approach, unless one of these servers can be ported to some other open
source RTOS that runs on the SoC.


Any thoughts on how this could be done easier? Whether it makes sense?

 -Tom

1. http://en.wikipedia.org/wiki/ATA_over_Ethernet
2. http://code.google.com/p/aoeserver/
3. http://code.google.com/p/qaoed/
4. http://code.google.com/p/ggaoed/