Hi, * Ruben Schwarz <r.schw...@sotec.eu> [151124 10:58]: > We are using yocto to build a custom linux image for our BeagleBoneBlack > based hardware. We are using a read-only root file system to prevent data > lost if power supply is lost. > Now we wan't to be able to update our device. If it is possiple we wan't to > use apt/dpkg to do this update. We set up an update server and everything > works so far.
Ok, so you're only mounting a standard file system read-only. > Following steps are done to do an update: > mount -o remount,rw / > apt-get update > apt-get upgrade > Everything works fine, new package versions are installed. After rebooting > the device and executing "dpkg -l" the old package version is listed. > Output of mount shows that there is tmpfs on /var/lib which hides the > /var/lib/dpkg folder. I guess that if you want this to work, you'd need to move the original /var/lib/dpkg folder out to some other in your file system. Then you can have that new folder mounted on top of your /var/lib tmpfs. That's probably the easiest way to solve your issue. > Is there an standard way how to update devices with read-only root file > systems? Anybody here who did something similar? Well, it depends. For consistency, I'm in the camp that prefers to do image-based upgrades. I.e. rewrite the whole rootfs; though that normallly requires that you're either switching between two alternative rootfs', or that you have a special maintenance/upgrade rootfs. Cheers, Anders -- Anders Darander, Senior System Architect ChargeStorm AB / eStorm AB -- _______________________________________________ yocto mailing list yocto@yoctoproject.org https://lists.yoctoproject.org/listinfo/yocto
