I just can't seem to sysupgrade my R6220, even when I used the previous version v18.06.3 to try and upgrade to v18.06.4 I hit the same wall.. I then tried to use the mtd method only to 'soft-brick' the router requiring the use of nmrpflash tool to re-flash original firmware and then flashing the new firmware, and succeeding doing it...
While I have seen other 'solutions' where you use already available snapshots to resolve the issue, there's a problem if you cannot get your firmware to upgrade, it could be there's an extra step to maybe build a .bin file from the .tar file... since the .tar file seems to cause the issue...
Tried the official .tar file from http://downloads.openwrt.org/releases/18.06.5/targets/ramips/mt7621/
sysupgrade /tmp/openwrt-18.06.5-ramips-mt7621-r6220-squashfs-sysupgrade.t ar Saving config files... Commencing upgrade. Closing all shell sessions. client_loop: send disconnect: Broken pipe
Router restarts and no success.
Running sysupgrade with a custom ImageBuilder build, this time with verbose output:
sysupgrade -v /tmp/openwrt-ramips-mt7621-r6220-squashfs-sysupgrade.tar Saving config files... etc/config/dhcp etc/config/dropbear etc/config/firewall etc/config/network etc/config/system etc/config/wireless etc/dropbear/dropbear_rsa_host_key etc/group etc/hosts etc/inittab etc/opkg/keys/1035ac73cc4e59e3 etc/opkg/keys/5151f69420c3f508 etc/opkg/keys/72a57f2191b211e0 etc/opkg/keys/792d9d9b39f180dc etc/opkg/keys/9ef4694208102c43 etc/opkg/keys/b26f36ae0f4106d etc/opkg/keys/b5043e70f9a75cde etc/opkg/keys/c10b9afab19ee428 etc/opkg/keys/d40651ed57ae87d1 etc/opkg/keys/dace9d4df16896bf etc/opkg/keys/dd6de0d06bbd3d85 etc/passwd etc/profile etc/rc.local etc/shadow etc/shells etc/sysctl.conf Commencing upgrade. Closing all shell sessions. client_loop: send disconnect: Broken pipe
Router restarts and I'm back to square one...
Does anyone know how to make this work without resorting to 'flash-ready' snapshots? since this does cause confusion, especially for anyone who uses the official documentation.