I want to upgrade my device to LEDE-17.01. There is one problem that it will lose all saved config evenif checking in keep config files. The command I execute: sysupgrade -c -v /tmp/lede-17.01.bin. It boot up normally, but lose all config files which I have changed on OpenWRT-CC, it is same as upgrade without save config files. besides, I try to run mtd -j /tmp/sysupgrade.tgz write /tmp/lede-17.01.bin firmware, and dump the firmware partition hexdump -C /dev/mtd3 > /tmp/firmware. I see the file of sysupgrade.tgz have wrote to jffs2 filesystem. I press "f" to enter failsafe mode and execute mount_root done. Those errors result:
root@(none):/# mount_root done
[ 14.270490] jffs2_scan_eraseblock(): End of filesystem marker found at 0x0
[ 14.278710] jffs2_build_filesystem(): unlocking the mtd device... [ 14.284877] done.
[ 14.286844] jffs2_build_filesystem(): erasing all blocks after the end marker... [ 116.137226] random: crng init done
[ 318.794926] done.
[ 318.796945] jffs2: notice: (391) jffs2_build_xattr_subsystem: complete building xattr subsystem, 0 of xdatum (0 unchecked, 0 orphan) and 0 of xref (0 dead, 0 orphan) found.
[ 318.857395] mount_root: performing overlay whiteout
[ 318.863954] mount_root: syncronizing overlay
[ 318.877639] mount_root: failed to sync jffs2 overlay
@JW0914 Thanks for your reply. The main question is that I don't want to copy backup files to PC or USB drive. sysupgrade with '-c' option will append the backup files to firmware partition with jffs2 filesystem. But I don't know why restore config is failed to upgrade to LEDE from OpenWRT.
Between backing up your settings, reconfiguring from scratch (with your backup in hand, so to speak) and dirty flashing 17.01, then hoping everything keeps working, and having to start digging when something does not, I'd really prefer the former.
Sure, it will take some time; but you'll be sure something didn't break silently along the way.
That is why I suggest you back them up on your client, then execute a clean flash and reconfigure using the old config files (it's just a tarball) as a reference. That way, you're sure to minimise any incompatibilities which might arise due to changes under the hood between 15.05 and 17.01.