On Sun, May 3, 2015 at 3:58 PM, Chris Morgan <chmor...@gmail.com> wrote: > We thought about the rescue/recovery approach as well. The issue was how the > system would recover in the field and how updates were handled. > > Consider that to update the full system image you'd have to download and > store that image to flash, unless you stored it somewhere, and if you were > going to store it you'd have to have extra space for that. For recovery > you'd have the similar approach of booting recovery but you could write > directly to the primary fs since you're booted to recovery. The trouble > there is download speed and connectivity. The system is down until you > download the update diff/full image and that could take some time. And the > system is down for that period. > > So we didn't see a path forward that would support slow connections plus no > down time. And we would still need some place to put the new image that was > guaranteed to be available which means it couldn't be used for application > or other data that had to be preserved across updates. With two rootfs > partitions we can download in place and take our time doing so. Plus no > special recovery image and no reserved area that is unused except during > update. We do have a full duplicate rootfs though. > > I see where you are going, for other use cases it may be better to have a > primary and a recovery. Our rootfs is around 200MB at this point. I don't expect my rootfs will be anywhere near 200MB. It's a deeply embedded, single function application. So the issues of memory size and bandwidth don't really apply for my particular application.
As I have thought about this more (driving to and from baseball games for my kids), I think what I was really wishing for was a Yocto standard/recommended Poky core-image-bootstrap image with appropriate hooks and configuration items to allow me to tailor it to my particular application. So far, I'm not sure how core-image-bootstrap differs from core-image-minimal, except for the additional packages and a custom rc.local I mentioned previously. So perhaps there isn't a need for such a beast, and I'll go roll my own bootstrap/rescue upgrade strategy myself. I'll go start a different thread with a specific question along that line now... --wpd -- _______________________________________________ yocto mailing list yocto@yoctoproject.org https://lists.yoctoproject.org/listinfo/yocto