On Mon, Oct 24, 2016 at 12:41 PM, David Riley via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
On Oct 24, 2016, at 11:51 AM, Neil Cherry via vcf-midatlantic < vcf-midatlantic@lists.vintagecomputerfederation.org> wrote:
It's not safe to power off without a shutdown on the RPi, if the TV's
usb
port shuts off, just as with any Linux system. People do it anyway, when they unplug the adapter on the RPi, but they are just lucky till their SD card get scrogged Dan
Dan it can be done, if we can setup the SD read only, turn off swap and any application that write to the SD (such as syslog). When we need to write the SD (for configuration) we can remount the SD as write.
Yes, this is the correct way to do it. I do it all the time for things like routers. It's considerably easier to do on something like OpenBSD than on modern Linux (because most modern Linux distributions like to have a lot of different read/write directories for systemd and the like), but it's still pretty doable with tmpfs overlays and periodic syncs to flash (just use a journaled filesystem and hope you're not syncing when the power goes out).
Updating the content is then another matter, but I highly recommend NFS for that purpose (rather than trying to swap out physical media). Connect your signage via Ethernet if you know what's good for you.
- Dave
I suppose if it's just a media player, where the video files are only reads. But many of my RPi's use File I/O often enough I also use the battery backup, its cheap, and RPI's use very little power So I have time to use shutdown And I heard the problems aren't strictly on Class 10 cards I see people on the forums with problems on Class 4 and 6 cards And I read not all SD cards have similar wear-leveling which can get corruptted on a power loss. Dan