Douglas McClendon wrote: > Martin Langhoff wrote: >> On Wed, Sep 9, 2009 at 4:26 AM, Douglas >> McClendon<dmc.su...@filteredperception.org> wrote: >>> My name is Douglas McClendon, and I created the ZyX-LiveInstaller which >>> appears >>> on track to becoming part of SoaS. I also can accept praise and blame for >>> the LiveUSB persistence feature I implemented for fedora a couple years >>> back, >> Good to have you on board! One thing we've found is that the overlay >> fs trick is neat but somewhat fragile. In brief - unclean shutdowns >> and "oops, I pulled out the stick" cases very often leave the USB >> stick unbootable. >> >> Of course, first step is fsck.vfat, but after that, we're completely >> lost. Hints would be more than welcome. Ideally, something smarter can >> be done during the boot itself or otherwise with a "repair" script. > > Unfortunately I don't have any easy answers. As someone who works on NDS
Ok, more hints as various vague theories start percolating through my memory. First disclaimer- I'm no fsck.vfat expert. Maybe there are options and ways to use it to more success than I've had, perhaps even targeted to the failure case at hand. But from a worst case perspective of assuming you always run grave risk of completely corrupted fat due to simple write interruption, you could go with an extra buffer layer in the devicemapper snapshot overlay. I.e. a second small overlay on a separate, intentionally 'volatile' partition. Then periodically (5min and/or user-tunable) write that back to main overlay on the less volatile main partition. And some amount of replication of those files/slices. Of course unionfs implemented LiveOSs are somewhat different, though actually I think the above maps pretty well to both the same problem and solution for that type of LiveOS. Or maybe subtle features of btrfs that I don't completely grok yet make this problem go away... Dunno... -dmc _______________________________________________ Sugar-devel mailing list Sugar-devel@lists.sugarlabs.org http://lists.sugarlabs.org/listinfo/sugar-devel