Wifi dies when using port scanner on client

Greeting. First, sorry for my bad English.

I have archer a7 and successfully installed openwrt 22.
I have a problem when using a port scanner like nmap the wifi suddenly disconnect for all the clients. Looking at my Android phone the wifi seems to be still alive but kicking out all the clients. My phone struggled to reconnect, it show connecting>saved in loop until it successfully connected after around a minute.

In syslog I can see hostapd AP-STA-DISCONNECTED.

Actually my problem is when I playing game LOL wild rift on my tablet the wifi keep disconnected. I can see in the game setting network test it has a wifi clients scan. Because I remember I do have a problem with port scan with my phone when scanning ftp server with mixplorer to look for my other devices the wifi suddenly disconnected also. So I figured out it was the culprit. Then I tried nmap, wifi also disconnected.

Maybe I'm dosing my router with port scan. Is there anyway to choke the port scan from the router side? Or maybe some other reason the wifi crashed. I can't figured out anything from syslog. There's nothing much there.
I have no problem with OEM firmware. Only after I installed openwrt.


  • What is running the port scanner/nmap? (is this a host on the network, or the A7 itself)
  • Does the problem occur for both wireless and wired connections? Or just wireless?
  • Does it happen for all wireless devices, or just some?
  • What do you need to do to resolve the issue?
  • Have you installed any additional pacakges onto your router?
  • What have you changed from the default configuration?