How can I reset my router after a bad '/etc/config/dhcp' change?

Installing and Using OpenWrt
1

I was trying to forward a particular IP to a particular device by MAC. I followed the instructions provided here. First I sshed into the router and edited the /etc/config/dhcp file by adding this to the end...

config host
        option ip           '192.168.0.49'
        option mac       'Whatever'
        option name     'Robot Brain'

But now when I restart the router the networks start but I get no internet and I can't ssh or log into the admin console. I tried resetting (holding the button for 30 secs) and everything else I can think of but no luck. The router is an Archer C5 v1 (https://openwrt.org/toh/tp-link/tl-wdr7500).

Is there any way to unbrick this thing?

2

30 seconds may be too long. Try this:

Turn on openwrt router for a minute.
Press Reset button for 10 seconds and 'immediately' release button as soon as LEDs change colour.

https://openwrt.org/docs/guide-user/troubleshooting/failsafe_and_factory_reset

1 Like
3

Tried for just 10 secs but I didn't see anything change color

4

I can push the button a lot on boot and get the sun (?) icon to flash but I still can't ssh and I don't see a gateway when I run ipconfig

5

The TFTP debrick worked I would recommend the youtube video Fi0pC_ON5Vo

6

if you are getting a flashing icon (which is probably a 'world'/globe as a symbol for the internet), you probably did manage to get failsafe mode working (hopefully). You have to manually set your IP address on your host computer.

IP address: 192.168.1.10 (anything other than 192.168.1.1, but within the subnet)
Subnet mask: 255.255.255.0
Gateway/Router: 192.168.1.1

Then try to ping and/or ssh into the router.

EDIT: looks like you got it sorted out a different way.

1 Like
7

Failsafe mode or TFTP recovery, as explained in detail in the wiki article that you linked.

8

I ended having to reflash using the TFTP(?) method.

9

If your problem is solved, please consider marking this topic as [Solved]. See How to mark a topic as [Solved] for a short how-to.

10

Try to connect with a fixed IP address, it might be that your router started but that your DHCP server didn't.

11

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