Diskless linux using SD card and ramdisk on 2GB FitPC2i?

[LEGOManiac]

Has anyone tried running Linux from an SD card, using (say) a 1GB ram disk so as to dispense with the hard disk? Is this even a sane idea?

I'm a bit concerned about the amount of heat the FitPC2i is producing, but I gather that a substantial amount of it comes from the hard disk and video. I want to use it as a Firewall/DNS/DHCP server and I don't care much about keeping extensive logs. I read in the manual that not connecting the video port saves about 20% of the energy. I'm not sure what the hard disk accounts for but I figure it's got to be fairly high too.

Does anyone know how to go about this?

[mwgrient]

I have never tried it because it will be a SLOW system...

[LEGOManiac]

Actually, I did some research on this and discovered PuppyLinux which does exactly this except it copies the linux file system to ramdisk and runs it from RAM, rather than the SD card. You are given the option of saving changes to the SD card on shutdown. It's mostly what I want but I'd rather have Ubuntu simply because all my other computers are using it, as is the server the FitPC2i is intended to replace.

[fly]

I have never tried it because it will be a SLOW system...

I am running from a CF Card connected via USB. After some optimization the system is fine and speedy.

Has anyone tried running Linux from an SD card, using (say) a 1GB ram disk so as to dispense with the hard disk? Is this even a sane idea?

I have an 1GB fitPC2 and did just that. I used a custom-built Slackware which occupied about 300MB RAM, add those 256MB of VRAM and you still have 512MB of RAM for traditional use. Doesn't sound much these days, but depending on the use case this is more than enough.

--

Ubuntu (not tested):
http://ubuntuforums.org/showthread.php?t=1603423
https://wiki.ubuntu.com/BootToRAM

[haseldow]

I've done extensive testing on running custom made Debian Live images from SD card on fit-PC2-D1G-C1100. For the purposes mentioned in the first post, this would work just fine.

I see no reason why you could not run Linux directly from the SD card without using a live build. There are a few considerations however. Writing to SD is slow and there's an limited amount of write/erase (rewrite) cycles so you should not use swap and be sure to use kernel parameters such as noatime. Also avoid extensive logging. Logs could be written to a ramdisk (or to /dev/shm).

The installation itself should fit in a couple of hundred MB.