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Linux Wall Warts Small On Size, Big On Possibilities
davidmwilliams writes "Every geek and technology lover will undoubtedly have stumbled across online adverts for tiny headless Linux-powered devices that are barely larger than the power point they plug into. What can you actually do with them? Plenty, it seems!"
Did it really need 3 pages? Nope.
I should put something clever here. Maybe someday.
My google-fu > than yours apparently...
http://lmgtfy.com/?q=linux+wall+wart
Plug computers are widely overrated. For the same price you can get a cheap home oriented NAS box like http://www.lacie.com/us/products/product.htm?pid=11384 with 1TB of storage that can be reflashed http://lacie.nas-central.org/wiki/Main_Page to do whatever you want.
I actually RTFA because I'm interested in these things... And found it a total waste of time. Let me summarize everything in it:
The small and cheap, low-power computer that you plug directly into the wall is actually a small and cheap, low-power computer. It has USB 2.0 (as can be clearly seen in all pictures of the device). You can install linux on it and do stuff that such a linux computer could obviously be used at: File storage, run FTP server, run apache, use it as SSH gateway... That's about the list of ideas mentioned in TFA.
Did anyone here actually find new information (okay, 3rd page has a bit of technical specs. Nothing unexpected, nothing that would have taken more than 2 minutes to google) or ideas in the article? If so, what were they? If I missed something essential, my bad... But this seems to contain zero information. Especially to someone who already has interest to such devices (obviously, if you've never heard of these "wall warts" ((Okay, I hadn't heard that name being used for these devices before)) before, everything there was new. Though I still believe that running ftp server or ssh gateway would have been about the first things you would have thought of yourself, too).
Plug computers are widely overrated. For the same price you can get a cheap home oriented NAS box like http://www.lacie.com/us/products/product.htm?pid=11384 with 1TB of storage that can be reflashed http://lacie.nas-central.org/wiki/Main_Page to do whatever you want.
If you don't need the storage as much as you need the always-on/low power processing, you can get a WRT54-based router that can be relfashed with Tomato or DD-WRT, then you can install optware. The Asus WL-500G has enough guts to run Asterisk while still doing its primary purpose. Or maybe a cvs, svn or other repository. All for maybe half the price of the Sheevaplug. And much more available. Of course, it doesn't have the wall wart form factor, for good or bad. And it's not quite as discreet, if that's a requirement.
I am not a crackpot.
I own a few of these devices. My first one has a eSATA port that I connected to a 5 bay sata port expander. That has been my network DHCP/DDNS/fileserver/printspooler/VPN endpoint/etc for a while now. The problem is that its hard to justify when compared with the recent firewall/wireless devices that have USB ports for exactly this reason. Sure I can get ~60MB/sec, absolutely outrunning anything attached via USB, but it cost about 3x as much to get there compared with just purchasing a $70 netgear and plugging in a dual drive USB raid array.
Plus, these things _REQUIRE_ hacking to get them to do a lot of stuff. I wasted days of my life trying to figure out why the JTAG interfaces didn't work as documented, or trying to boot kernels that didn't come with the devices. Or even consistently boot off USB instead of internal flash. This would be fine, except they are hardly open devices. Much of the time wasted turns out to be endless reverse engineering closed portions of the device. Marvell publishes a fair amount of the documentation for them, but I quickly found, time and time again, that the information I needed wasn't available.
So, In the end, for low level stuff things. The AVR butterfly an similar devices are far better hacking platforms, and on the higher end its hard to ignore the atom nettops or dozens of very nice single board computers that are far more powerful for not much more money.
I have had 4 SheevaPlugs. Two died on me, one was replaced and the other I had to buy a replacement PSU. They are touted as plugging into a wall socket, but if you do that they are pretty precarious, and if you plug them in via a power cable, then they don't stack nicely. I prefer the PC Engines Alix boards (http://pcengines.ch/alix.htm) - based on the AMD Georde with 255MB of memory they seem to be as fast as a SheevaPlug (I read somewhere that the Kirkwood processor only has a 16-bit data bus whereas the Geode has a 32-bit data bus). The Alix systems have a nice Aluminium case and run cool and sweetly - a German company nrg-systems.de, sells cases that will take a 2.5" hard disk, which draws an extra 2 Watts above the 8-10 Watts that the base system uses. I have 3 Alix systems: one as my firewall, one running my Asterisk PBX and the other running Exim, Dovecot, NFS, Samba, etc. The three systems together draw less than 30 Watts, replacing a pair of 150 Watt tower systems that ran 24x7 saving enough on my electricity bill to pay for themselves in just over a year.
I'm using these devices now for R&D work. We started with the Sheeva plug, now the Guru plug. The devices are okay. If you are looking for a COTS general purpose computer, the price, size and capability cannot be beaten. If you have more specific needs, particularly consumer needs where you can give up size as a constraint, there are many other cheaper alternatives.
That said, if you open up one of these devices, the thickness of the "wall wart" is half power supply, and a lot of the space is allocated to thermal design (heat sink, space for airflow). If you don't need their (crappy) power supply, replace it with a 5 V DC-DC converter and you can run it in your car or in your custom R&D device like we are. Very few low cost (small, low power) GigE devices exist now. These are just about the only ones. Downside is that there is NO support (oh, I'm sorry, "community support"... not okay for corporate use). You have to go it alone if you want to do something that nobody else has done.
Globalscale (makers of the Sheeva/Guru plugs) are supposed to be releasing a GuruPlug "Display" device which has an HDMI port. It sounds cool, but based on my experiences buying the "Server" version on spec, wait until it is not just vaporware. They said that the "Server" version would include some things that aren't actually pinned out (so if you want, say, an I2C interface, you have to be prepared to go digging around on the circuit board, then you might have to deal with building a custom kernel, then you might have to pray on your knees before the dark god of fab, etc.).
And forget about using this as a portable device. Power draw is low but it still sucks down the juice if you're using it do actually do anything. And the ARM5 core does not, as I recall, support floating point operations, so they're emulated (at reduced speed). And last but not least you're going to be cross-compiling everything, or hooking up a hard drive so you can install a precompiled gcc and making less-common things from source.
All in all, are these show-stoppers? No. I'm still using a few of these for various jobs, like one which is going to go get pelted around in the ocean, and they're great if you can withstand the negatives. I have $200 worth of batteries to run it and a custom kernel build (and a separate board for the I2C interface, thanks a lot you jerks at Globalscale)... took a while to get going but it mostly does the job.
Just my $0.55 (US inflation, 1774-2008, for $0.02)
This has been covered on slashdot before. 1.5 years ago.
$100 Linux Wall-Wart Now Available
+4 Informative? More like Uninformative.
How many more years will slashdot have an off-by-one error on your Score in your profile?