How do you reset a DNS server?

Resetting DNS is useful when the current resolver settings are wrong, the router has bad entries, or a device has cached outdated network configuration.

Step-by-step solutions

1. Open the network adapter settings on the affected device.
2. Remove manually configured DNS servers or replace them with known public DNS values.
3. Set the adapter back to automatic DNS if you want to test the ISP defaults.
4. Restart the connection or reboot the device.
5. Flush DNS cache after the change.

Useful commands

Windows

netsh interface ip set dns name="Wi-Fi" dhcp
ipconfig /flushdns

macOS

networksetup -setdnsservers Wi-Fi empty
sudo dscacheutil -flushcache

Linux

sudo resolvectl revert eth0
sudo systemd-resolve --flush-caches

If cache corruption is the real issue, clear DNS cache is often enough. If the broader problem is still unresolved after a reset, return to how to fix DNS server problems and continue the diagnostic flow.