Since I was looking up which boards would make a proper NAS and home automation hub, I figured I might as well summarize the options in a post.
Requirements for a proper NAS:
- Gigabit Ethernet
- SATA that is not a crappy USB->SATA chip
- Armbian-supported
That last one is because otherwise the options are much more numerous and scattered, and the previous requirements become vague (e.g., you could even just take out a netbook's motherboard and run it standalone).
Also, you could use an A80 board (USB 3.0) but I believe none are supported by Armbian, same goes for R40 (has SATA), so this leaves us with these A20 boards that also have GbE:
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Banana Pi
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Banana Pi+
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Cubietruck
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Lamobo R1
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Olimex Lime 2
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Olimex Lime 2 eMMC
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Orange Pi
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Orange Pi mini
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pcDuino3 nano
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Clearfog Base
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Clearfog Pro
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CuBox-i
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HummingBoard (Pro & Edge)
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Udoo Quad
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The prices and availability for these boards is as follows:
Lamobo R1 (out of stock / discontinued)
Orange Pi (renamed? / out of stock / discontinued)
Orange Pi mini (renamed? / out of stock / discontinued)
According solely to the above, and disregarding other board differences/features, for a simple LAN-connected NAS hard drive that occasionally pulls a few GPIO pins high or low for automation, the Banana Pi looks like a good option.
Maybe I'm overlooking things, and maybe any of those prices are wrong; since this is a forum anyone is free to correct me and I'll try to update this OP in case the thread grows (and I remember to check back down the road).
Edit: a great read is this wiki article, some considerations: clock speed and CPU governor matters a lot more than in x86 (doing other stuff during transfers might be a no-no) and Gigabit Ethernet might mean "USB 2.0 speeds, but in a RJ45".
Side note: it would be nice to have a list of boards somewhere with feature matrices and prices/links, not sure if such a thing exists.
Edit: added Clearfog Base/Pro, CuBox-i, HummingBoard Pro/Edge and Udoo Quad as per suggestion)