[vcf-midatlantic] TVs installed!

[Dan Roganti]

On Mon, Oct 24, 2016 at 12:41 PM, David Riley via vcf-midatlantic <
vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:

> On Oct 24, 2016, at 11:51 AM, Neil Cherry via vcf-midatlantic <
> vcf-midatlantic at 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