Hi Andy, Thanks for the response. On 1/27/20, Andy Pont <andy.pont@xxxxxxxxxxxxxx> wrote: > JH wrote... > >>That the same problem of missing busybox was not just occurred during >>the device running in the middle of operation, it was also occurred >>during booting image from NAND, I saw several times that the first and >>second cycles of booting image from NAND were working well, then some >>following booting process would be crashed by missing busybox, then >>could not run whole shell commands. I have been pondering if it could >>be caused by NAND issue or network virus / fishy? Appreciate any >>clues. > The first step is for us to understand what “missing” means? Have you > got any mechanism (U-Boot, SD card boot, etc.) that will allow you to > mount and look at the contents of the NAND file system? Means that busybox was not there anymore, it mysteriously lost, all shell commands would no longer available. It cannot to run mount or any shell commands. There was two scenarios when that happened: - In the middle of running, the device all of certain could not run shell commands and failed mysteriously - During the u-boot booting kernel process, there were full errors of failing shell commands. Let me make it clear, that booting error did not occur in the first or second kernel booting after the new image installation, it happened in the following kernel booting, but there was nothing to delete busybox accidentally, busybox was just mysteriously disappeared. Because I could not run ls, I did not know if there are other things missing. If you ask how I could know the busybox was missing, I ran the zImage-initramfs to boot the linux in RAM, then mount the ubi0 to find out busybox was gone. > If you look at the /bin directory (ls -la /bin/busy*) what do you see? > Have the files been deleted? Truncated? Zero length? Could not run ls or any shell commands when the busybox was missing. > What file system are you using on the NAND flash? How are the devices > being reset during the various boot cycles? If it is a hardware reset > then some file systems are less resilient to it than others but I would > expect in that case more fundamental boot issues. UBIFS, most device reset or boot cycles were calling halt or reboot, but it sometime it could just use power cycle. Thank you. Kind regards, - jh ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/