OpenWrt on MR33, Fail. "Cannot save config while running from ramdisk"

Hi I'm crossing my fingers that somebody with a more experienced eye can give me a clue as to how where this is going wrong. As a disclaimer, this is all new to me, everything i know about linux and openwrt I have learned in the last 24 HRS but i dont think i have done too badly. :slight_smile:

I have managed to upload the sysupgrade.bin file to a Meraki MR33-HW but it throws an error message (Cannot save config while running from ramdisk.) then logs me out, then restarts (green light flashes then stays on) then once its up again i can navigate in to 192.168.1.1 and log in to openwrt, so far so good, but when I kill the power and reboot it the web interface cannot be contacted on 192.168.1.1 or http://192.168.1.1/cgi-bin/luci

I can ping 192.168.1.1 so i know that the connection is alive.

I think Ive read all the posts with the same error mentioned but I found nothing that I can see is applicable.

I downloaded the file collection for the MR33 from google drive.
I have this with the aid of a CP2102 adaptor to interupt the bootloader with ubootwrite, upload the ITB file, ssh in to root on the MR33 AP, as per instructions removed all but the APT partition, created the openwrt fallback partiton. upload the sysupgrade file to /tmp (version 18.06) and it returns the message ;

root@OpenWrt:/tmp# sysupgrade -v openwrt-18.06.1-ipq40xx-meraki_mr33-squashfs-sysupgrade.bin

Cannot save config while running from ramdisk.

Commencing upgrade. Closing all shell sessions.

Connection to 192.168.1.1 closed by remote host.

Connection to 192.168.1.1 closed.

me@me-Latitude-3330:~/Documents/mr33files$

the only way i can see to get back in is to repeat the process. I called ubinfo after the last failure and it shows that it has created partitions on the AP.

-----------------------------------------------------
 OpenWrt 18.06.1, r7258-5eb055306f
 -----------------------------------------------------
=== WARNING! =====================================
There is no root password defined on this device!
Use the "passwd" command to set up a new password
in order to prevent unauthorized SSH logins.
--------------------------------------------------
root@OpenWrt:~# ubinfo -a | grep -e "Volume ID" -e "Name"
Volume ID:   0 (on ubi0)
Name:        part.old
Volume ID:   1 (on ubi0)
Name:        part.safe
Volume ID:   2 (on ubi0)
Name:        rootfs
Volume ID:   3 (on ubi0)
Name:        rootfs_data
Volume ID:   6 (on ubi0)
Name:        ART

Can anybody help? My heartfelt thanks are forwarded in advance.

# sysupgrade --help | grep save
	-n           do not save configuration over reflash
# sysupgrade -n <img>
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hello, thanks for replying, could you tell me what -n is preventing from happening? Is flashed image being re-rewritten by the AP on hard reboot? Just trying to understand whats going on thx.

Hi, its been a while, life got in the way :). I have tried the "sysupgrade -n" switch but I'm still having problems

root@OpenWrt:/tmp# sysupgrade -n -v openwrt-18.06.1-ipq40xx-meraki_mr33-squashfs-sysupgrade.bin
Commencing upgrade. Closing all shell sessions.
Connection to 192.168.1.1 closed by remote host.
Connection to 192.168.1.1 closed.
me@me-Latitude-3330:~/Documents/mr33files$ 

The MR33 blinked its green LED and then it stayed on and as before I could access the web interface on 192.168.1.1

The more positive response hasn't solved the problem when cold booting. when power is turned on it issues an ip to the attached PC in the 192.168.1.x range, I can ping 192.168.1.1 but I cant get to the web interface on 192.168.1.1 http or https

does anybody have any ideas or tips? did I miss something? again thanks in advance.

OK, just for posterity I'll write up the procedure I used to get it working, although I'm not sure exactly how or why it started working, perhaps this will be of use to somebody or perhaps somebody can explain why what I did, did and didnt work.

after the "sysupgrade -n" failure I went back to the "sysupgrade -v" command and that didn't work either, I then tried running it from the /tmp ramdisk that didnt work either so i switched back to root and ran it with the -n switch and suddenly;


root@OpenWrt:/tmp# sysupgrade -n -v openwrt-18.06.1-ipq40xx-meraki_mr33-squashfs-sysupgrade.bin

Commencing upgrade. Closing all shell sessions.

Connection to 192.168.1.1 closed by remote host.

Connection to 192.168.1.1 closed.

me@me-Latitude-3330:~/Documents/mr33files$

It worked! Until I pulled the power and cold rebooted it. Then it would issue an IP address, i could ping 192.168.1.1 but I couldnt gain access to the Luci web interface.

up until now I had been using the file collection that was provided in the openwrt download zip, version 18.06.1 i struck me that if i ever got it working it would be good to have the latest version 19.07.2, so i went through the rooting process again and tried flashing 19.x and it failed like the very first time. At this point I was ready to accept that it wasnt going to work.

I thought I’d give it one more look over before I threw in the towel and cold booted it and- blow me down! The web interface came up! and so far it seems to be working without a problem. I’ve set it up as a AP and its working flawlessly.

So Ive got no idea why the flash worked that one time with v18 or why it flashed v 19 when it said it couldnt when running from ramdisk.

Perhaps there was a bug with v18 that was resolved by v19?

Also what happens if somebody pushes the physical reset button? Is it worth putting superglue it so that nobody can?

As I like to point out, if you're having trouble getting LuCI to load, but ping and/or ssh works, and it's not a snapshot build (those don't have LuCI)-- try clearing your browser cache. This is especially important if you've been using the same browser to access a different system at 192.168.1.1.

Booting the initramfs is to provide a platform to flash the sysupgrade. The "cannot save configuration" message is normal. There's really no configuration to save.

Pressing the physical reset button (after OpenWrt is fully booted) should either do a simple reboot or a reset to OpenWrt defaults if the button is held down for more than 5 seconds.

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Thanks, I'll be sure to bear that in mind the next time around.