[Solved] MR33 Flashing Issue

I am trying to install OpenWRT on a Cisco MR33 that never got connected to the internet, I have it for 1+ year already.

When I ran the ubootwrite.py script, this is the output I received:

Prompt is 'UNRECOGNIZED COMMAND LOGGED TO CLOUD SERVERS.
<Meraki> '
Progress 0.2%
, 0.3kb/s
, ETA 516.0s
...
Progress 99.5%
, 0.3kb/s
, ETA 2.0s
Progress 99.7%
, 0.3kb/s
, ETA 1.0s
Progress 99.9%
, 0.3kb/s
, ETA 0.0s
Progress 100%
File successfully written. You should run 'crc32 80500000 00029f20' on the modem and the result must be 68cea086.
To copy from RAM to flash, unprotect flash: 'protect off all'...
Then erase flash: 'erase b0500000 +00029f20'.
Then copy from RAM to flash: 'cp.b  80500000  b0500000 00029f20 '.

I did not get an IP address nor a tftp server was listening on the device. So I ended up rebooting it.

Now at every other boot, I can telnet my way in. However the ubi commands do not work as described, seems there is only one /dev/mtd* device.

I never was able to upload the FIT uImage, and sysupgrade of the sysupgrade.bin image fails

# sysupgrade -v openwrt-ipq40xx-meraki_mr33-squashfs-sysupgrade.bin
openwrt-ipq40xx-meraki_mr33-squashfs-sysupgrade.bin is not a valid FIT image
Image check 'platform_check_image' failed.

dmesg output here: https://pastebin.com/UWMMJmZa

Possibly need
http://downloads.openwrt.org/releases/18.06.0/targets/ipq40xx/generic/openwrt-18.06.0-ipq40xx-meraki_mr33-initramfs-fit-uImage.itb

Yeah ok... where do I put that file ?

Also, there are no /dev/ubi* devices present... I'm kind of lost

Use it in place of

@mathieu : still stuck? did you use the procedure and files found here: https://drive.google.com/drive/folders/1jJa8LzYnY830v3nBZdOgAk0YQK6OdbSS (link from https://openwrt.org/toh/meraki/mr33) ?

I restarted the whole process from scratch, using the ubootwrite.py in the google drive this time, and it worked out properly! Yay!

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