So this is just a very small post that I wanted to make because… why not.
I recently tried to flash freetz-ng onto my FRITZ!Box Fon WLAN 7240, but corrupted my firmware in the process. I tried to recover using the AVM recovery tool, but it just didn’t pick the box up.
What ended up happening, as i’ve later realized, is that the bootloader’s environment variables got messed up.
The Solution
I just needed to reset the variable to the correct value. I connected to the box over UART and ran printenv to get the current vars.
For those wondering, the baudrate is 38400 baud.
This gave me the following list:
HWRevision 144
ProductID Fritz_Box_7240
SerialNumber 0000000000000000
annex B
autoload yes
bootloaderVersion 1.484
bootserport tty0
cpufrequency 360000000
firstfreeaddress 0x946BD89C
firmware_info 73.06.06
firmware_version 1und1,1
flashsize 0x01000000
jffs2_size 16
maca [REDACTED]
macb [REDACTED]
macwlan [REDACTED]
macdsl [REDACTED]
memsize 0x04000000
modetty0 38400,n,8,1,hw
modetty1 38400,n,8,1,hw
mtd0 0x90000000,0x90000000
mtd1 0x90020000,0x90F80000
mtd2 0x90000000,0x90020000
mtd3 0x90F80000,0x90FC0000
mtd4 0x90FC0000,0x91000000
my_ipaddress 192.168.1.1
prompt Eva_AVM
provider
ptest
req_fullrate_freq 120000000
sysfrequency 120000000
urlader-version 1484
usb_board_mac [REDACTED]
usb_device_id 0x0000
usb_device_name USB DSL Device
usb_manufacturer_name AVM
usb_revision_id 0x0000
usb_rndis_mac [REDACTED]
wlan_key [REDACTED]
The problem was the value my_ipaddress, which was set to 192.168.1.1.
This is standard on most routers, but on AVM routers, the standard it 192.168.178.1
I’m not entirely sure what set the variable to that, but to fix it I just had to run this:
setenv my_ipaddress 192.168.178.1
And yeah, that fixed my issue of not being to reflash the router. Thanks for reading this little post!