Can’t get Fritzbox 4040 to enter Failsafe mode

[ErikOW]

After upgrading from 22.03.6 to 23.05.2 I messed up the configuration of my Fritzbox 4040 router using LuCI. Since I had previously been able in 22.03.5 to enter failsafe mode I was confident this could still be done.

However, after rebooting it’s been impossible for me to achieve this again. Immediately after reboot all 5 LEDs light up, then the power LED remains on for some time, flashes twice after which the power LED remains on, switches off and after some more time comes on again to remain on. No other LEDs. During this process I have my desktop connected via LAN1 port and set it’s IP-address to 192.168.1.2 (just like immediately after the upgrade process which was successful as far as I can tell).

So no fast flashing LEDs indicating the moment to press a button.

Any clues?

[tomtom]

I've never managed to enter failsafe mode on both of my 2 FB4040s.
As I have serial console access I didn't care about that.
Why not simply trying to re-install the openwrt-23.05.2-ipq40xx-generic-avm_fritzbox-4040-squashfs-eva.bin ?

[ncompact]

I can recommend assigning one of the two buttons on the router to perform the required functionality...

for example:

uci show | grep button
system.@button[0]=button
system.@button[0].action='released'
system.@button[0].min='0'
system.@button[0].max='3'
system.@button[0].button='rfkill'
system.@button[0].handler='logger "button WLAN push 0-3s; exec /root/switch_wifi"; /root/switch_wifi'
system.@button[1]=button
system.@button[1].action='released'
system.@button[1].min='30'
system.@button[1].max='100'
system.@button[1].button='rfkill'
system.@button[1].handler='logger "button WLAN push 30-100s; exec /root/repair_network"; /root/repair_network'
system.@button[2]=button
system.@button[2].button='wps'
system.@button[2].action='released'
system.@button[2].min='0'
system.@button[2].max='3'
system.@button[2].handler='logger "button WPS push 0-3s; exec /root/switch_wifi"; /root/switch_wifi'
system.@button[3]=button
system.@button[3].button='wps'
system.@button[3].action='released'
system.@button[3].min='30'
system.@button[3].max='100'
system.@button[3].handler='logger "button WPS push 30-100s; exec /root/repair_network"; /root/repair_network'

you see:

Debug general information

I would like to know if I am unable to ssh to a router with openwrt installed or to connect via an http or https connection which commands to save to debug the problem and find a possible solution. I currently have a hardware button configured to execute a script in the hope that hardware-wise it will still execute. it could be useful to save the files on a usb storage, but I thought that if there are problems accessing the storage the files would not be written, so I opted for writing on the …

[ErikOW]

Although I can ping the 4040 when the WAN is connected to my modem, I have no access at all since I had already confined ssh and LuCI access to LAN only. However, LAN is inaccessible due to wrong config.

I can still try the first time installation of OpenWrt firmware but I doubt whetehr my desktop will get an IP-address to start this process in the curren state.

[ErikOW]

Thanks ncompact but with no access to the router whatsoever, this is not going to help me now.

[ncompact]

you will have to reinstall as per the guide:

AVM FRITZ!Box 4040

[ErikOW]

Following the first-time install instructions did indeed work! Thank you tomtom en ncompact. I used the fritzflash.py route which normally requires a few attempts before it succeeds.

However, the failsafe mode still only works on 22.03 and no longer on 23.05. I'll file a bug report for this.