Can't flash or factory reset

I tried installing OpenWRT and seemed to have messed something up. Now whenever I start the device, factory reset it (3 lights) or try to flash it with a USB stick (4 lights), only the power light and the PCI2 light remain on.

I know that my best bet is to get a serial cable and debug it from there. The issue is, I ordered one, but considering the current situation, I don’t know if and when it will arrive. In addition, my old ISP is about to turn off my connection. So I’m looking for potential alternative ways to fix this.


Unless the device is an Omnia 2019 | 2020 model (CZ11NIC23) that shipped from factory with a u-boot version supporting [1]

5 LEDs: Unsecure SSH on 192.168.1.1 (Omnia 2019 and newer)

you would need to wait for the serial cable to arrive since that particular u-boot version has not been made available for other TO hardware revisions (CZ11NIC13 | CZ11NIC20) than the aforementioned.

In either case, if you want to re-install TOS (4-LED medkit via USB) instead of OpenWrt, you would need to


[1] https://docs.turris.cz/hw/omnia/rescue_modes/

It’s older than that. Does that mean, that I have absolutely no course of action but to wait for my cable to arrive?

Unfortunately u-boot image versions are currently not consistent across the various TO hardware revisions and thus

5 LEDs: Unsecure SSH on 192.168.1.1 (Omnia 2019 and newer)

is not available on CZ11NIC13 | CZ11NIC20.

has not been responded to by developers.


You would need to gain terminal access (ssh) via ethernet cable, in lieu of a serial cable, to the device in order to modify the bootloader environment variables, that if you want to return to TOS instead of OpenWrt.

The boot env reset command from ssh is slightly different than with the serial connection (not sure whether it is supported since it requires a binary from the uboot-envtools package):

fw_setenv bootcmd 'env default -f -a; saveenv; reset'

After reboot you could then attempt TOS medkit installation.

OpenWrt provides documentation on reset | rescue | recovery from botched firmware installations that may provide a way of connectivity other than the serial cable.