Failsafe

Intro

Failsafe is the short name for the RAM bootable rescue image for APF boards (APF6 only for the moment). It is a Linux kernel + minimal initrd image all packed together in a standard apf6-linux.bin.

Installation

Generate it

$ make apf6failsafe_defconfig
$ make
$ cp buildroot/output/images/apf6-linux.bin /tftpboot/

Launch it

BIOS> run ramboot

Cool stuff that can be done with it

apf-config

# apf-config

• check eMMC filesystem

Backup eMMC rootfs

• you need a network connection with a server that can receive the backup (for example with NFS, here mounted on /mnt/nfs/):

# dd if=/dev/mmcblk2 bs=512 count=7733248 conv=noerror,sync | pv | gzip -c -9 > /mnt/nfs/root.bak.gz

• wait some minutes until backup is done ;-)

Restore eMMC rootfs from backup

• same principle:

# gunzip -c /mnt/nfs/root.bak.gz | pv | dd of=/dev/mmcblk2 conv=sync,noerror bs=128K