I thought that some settings on my dumb AP were wrong and may have been causing a reduction in speed and a loss of WAN access, so I decided to re-set the device and set it up from scratch while following the instructions closely.
I am following these instructions:
I established an Ethernet connection to the unit. I re-set the unit by using the re-set button. The first thing to do after a re-set is to change the IP address from 192.168.1.1 to 192.168.1.2. When I try to do that, luCI reports that the connection with the unit was lost, so the changes will be rolled back. If I force the changes, I cannot access the unit at the IP address in a browser.
How can I change the IP address and access the unit at the new address?
I also cannot SSH into the unit. I receive this message:
WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the ED25519 key sent by the remote host is
[redacted].
Please contact your system administrator.
Add correct host key in /Users/rick/.ssh/known_hosts to get rid of this message.
Offending ED25519 key in /Users/rick/.ssh/known_hosts:1
Host key for 192.168.1.1 has changed and you have requested strict checking.
Host key verification failed.
How do I get past that problem? I have no record of a host key. I don't know how to add a host key to a file. Where is strict checking set?
The unit is a Cudy WR3000S v1. It was running 25.12.3. I downgraded to 25.12.2 because I wondered if the switch to 25.12.3, which I made in the last two days, could have caused some of my problems.
I have no record of a host key. I don't know how to add a host key to a file. Where is strict checking set?
So I don't know what the correct host key is or how to add it to a file. What should I do? Can I disable strict checking somewhere? Or do something else?
That's why I said you should delete it.
You don't have to know the new one, only kill the old one.
Deleting one too many (if we assume you've got several) isn't a problem, since they get readded next time you connect.
That ssh command let me in in to the router. The other problem remains: the change in IP address gets rolled back, I force the change, then the unit is not accessible from a browser at either the old IP address or the new one.
Pay particular attention to the fact that the IP address in 25.12 should be entered with CIDR notation (i.e. 192.168.1.2/24). Failing to enter the subnet size will cause the device to become unrechable.
I wondered about that, but stuck with the instructions. In any case, changing the IP address to 192.168.1.2/24 had the same result. The router is still unreachable by ssh and by browser.
I went through the whole process again so I could write down exactly what I am doing and exactly what happens. This time, it worked. I have no explanation because I am confident that I used the same steps that I used earlier today. But the additional caution needed to write everything down may have helped me avoid an error or an oversight.
The dumb access point is back up and seems to be functioning properly.
Changed address by: Network > Interfaces > edit lan > set IPv4 address to 192.168.1.2/24 > save > save & apply
My computer had the same IP address before and after the change: 192.168.1.167. This time, anyway. I don't know about my earlier attempts.
The process worked without me doing that.
Can router hardware have intermittent problems?
Could 25.12.3 have caused the slow speeds and loss of wan access that led me to do this work? I am wary of installing it. 25.12.2 is on the router now.
I cannot tell you how grateful I am for the people who develop OpenWrt and help other people use it. Thank you.
Could someone update the instructions to show that CIDR notation is needed?
Also, the warning that I received was different from the "configuration change" warning. Changes were rolled back after 90 seconds, then I had to "apply unchecked".
Note: in OpenWrt 25.12 and main/master snapshots, the default IP address notation combines the netmask line to the ipaddr line as a CIDR notation: 192.168.1.2/24 . With that notation you do not need a separate netmask line. The CIDR notatino is also supported by 24.10.
