[HOWTO] Recovering a soft bricked EAP615-Wall


Well... I somehow soft-bricked a (luckily spare) EAP615 device after a snapshot install from April 26th so decided to try out to restore this device with serial access


I used following documentation to verify what was needed to go through the process
-[HOWTO] Installing OpenWrt on Sophos AP 55 and AP 100

Eventually I bought following hardware
-AZDelivery CP2102 USB to TTL Converter HW-598
-Dupont Jumper cable (Male-Female) 10cm for Breadboard
-USB extension cable

And installed following software on my laptop (ubuntu)
-tftpd and tfp

Opening the EAP615-Wall was somewhat difficult but I succeeded luckily without breaking plastic parts


  • download initramfs-kernel.bin and sysupgrade.bin
  • assign laptop ip netmask
  • copy initramfs-kernel.bin to /srv/tftp and test if tftp works
$ tftp
tftp> get initramfs-kernel.bin
  • laptop: connect utp with PoE switch and CP2102 with EAP615

  • laptop: start terminal and enter
    $ sudo screen /dev/ttyUSB0 115200
  • EAP615: connect utp with PoE switch to power up the device
  • laptop: in serial terminal interrupt U-boot process and boot initramfs-kernel.bin
tftpboot 0x84000000 initramfs-kernel.bin
  • laptop: start a new terminal and enter
$ scp -O ./openwrt-sysupgrade.bin root@
$ ssh root@
root@OpenWrt:~# cd /tmp
sysupgrade openwrt-sysupgrade.bin

=> this will show few scary messages like

Cannot save config while running from ramdisk.
Fri Mar 22 22:16:12 UTC 2024 upgrade: Commencing upgrade. Closing all shell sessions.
Command failed: Connection failed

but when you look in the serial terminal you should now see the image being written, followed by a reboot