Zyxel RN7101 stuck in recovery (initramfs) mode

[cbdp]

Hello everyone. My first post and sadly I'm having trouble even getting openwrt installed on this device.

I failed to follow the instructions (sorry if that's the reason for why it failed) on the openwrt site, where I got the links to the images from. Instead I started by uploading the recovery firmware through the OEM web interface. After that, it booted in recovery mode and I carried on with installing the upgrade image. However on the next boot (and every reboot since), it boots again in recovery mode. I have read some posts where such problems are described, but the problems they were facing back then seem to have been resolved since.

Is anyone able to shed a light on my conundrum and point me in the correct direction for solving the problem?

Cheers,
Carl

[frollic]

see if Method to flash any NR7101 works for you.

[cbdp]

Thanks for pointing me in that direction frollic. I hooked up to the serial console and tried out zycast.

./zycast -i eno1 -t 50 -f openwrt-22.03.5-ramips-mt7621-zyxel_nr7101-squashfs-sysupgrade.bin

Multiboot Listening...                                                                                                                                                                                                                      2Receive first multiboot packet

Received RAS packet ID: 0x0871checksum bad                                                                                                                                                                                             0x1252checksum bad                                                                                                                                                                                                                           0x1946
Roll back to receive previous RAS packet ID: 0x0042
gEngCleanROMD = 0

------MultiBoot Download Finish------
Upgrading Ras...

Upgrade firmware from memory 0x89140000 to flash 0x00140000, file length 6625855, file type=1
RAS upgrade done!

Firmware upgrade fail !
Upgrade firmware fail!!

Any ideas?

Cheers,
Carl

[cbdp]

Reduced the delay to 4 and then it went through without checksum errors, yet the upgrade failed.

./zycast -i eno1 -t 4 -f openwrt-22.03.5-ramips-mt7621-zyxel_nr7101-squashfs-sysupgrade.bin

Multiboot Listening...                                                                                                                                                                                                                      2Receive first multiboot packet

Received RAS packet ID: 0x1946
Roll back to receive previous RAS packet ID: 0x03e1
gEngCleanROMD = 0

------MultiBoot Download Finish------
Upgrading Ras...

Upgrade firmware from memory 0x89140000 to flash 0x00140000, file length 6625855, file type=1
RAS upgrade done!

Firmware upgrade fail !
Upgrade firmware fail!!

[cbdp]

I was certainly not expecting this, but I just flashed it with the latest OEM and as far as I can see, it worked. At least the Zyxel WebUI is there again and I've logged in, so at least the device is not bricked.

./zycast -i eno1 -t 4 -f 100ABUV8C0.bin

Thanks again for pointing me in the right direction, frollic.

Cheers,
Carl

[Lynx]

Hopefully @bmork can help you get OpenWrt on this device. I have one and all works perfectly. But I'm not so savvy with firmware flashing particulars. It seems this device is pretty robust on terms of bricking - I haven't seen any report of irrecoverable bricking.

[bmork]

I suspect the problem was that OEM flashed OpenWrt to the second system partition and set BootingFlag accordingly. This will work fine with the initramfs. But sysupgrade will install OpenWrt to the first system partition, and will not work unless the BootingFlag is set to 0.

The dual firmware support was not enabled in the OEM firmware I initially had when adding support, so I was unaware of this at the time. Support was added later, but might be missing in eelease-images. There was also an issue with uboot-envtools missing from prebuilt initramfs images due to DEVICE_PACKAGES being ignored for initramfs. This affects the sysupgrade fix. So you'd either need a "new enough" (don't have an exact version, but probably not anythiing released) initramfs, or build it yourself, to make the OEM web-install failsafe.

Too late now, but it would be interesting to see the output of

fw_printenv BootingFlag

after booting the initramfs which failed to sysupgrade. Or, snce fw_printenv probably would be missing if this was the problem:

strings /dev/mtd1

[cbdp]

Thank you bmork, for the zycast tool, it saved my a$$.

Yes, I had seen errors which indicated that uboot-envtools were missing.

I may make another attempt at flashing later, but I suspect it will be a while until. Yesterdays attempt took more time than I had (: