How do you reset a DNS server?

March 04, 2026 · 7 min read

Quick Answer

Resetting a DNS server usually means removing bad custom resolvers, restoring automatic network settings, or replacing a failing resolver with a known good public DNS service.

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DNS is useful when the current resolver settings are wrong, the router has bad entries, or a device has cached outdated network configuration.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

Open the network adapter settings on the affected device.
Remove manually configured DNS servers or replace them with known public DNS values.
Set the adapter back to automatic DNS if you want to test the ISP defaults.
Restart the connection or reboot the device.
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.

FAQ

Does resetting DNS delete files or apps?

No. Resetting DNS changes network resolution settings and cache state, not your personal files or installed software.

Should I use automatic DNS after a reset?

Automatic DNS is a good baseline for testing, then you can move to a public resolver if the ISP DNS performs poorly.

Can a router store bad DNS settings?

Yes. A router can hold incorrect manual DNS entries or be changed by malware or misconfiguration.

What public DNS is safest to test with?

Cloudflare, Google Public DNS, and Quad9 are all safe mainstream choices for troubleshooting and comparison.

Test your DNS now

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