Encountering a DNS issue can halt your entire online experience, preventing you from accessing websites even when your internet connection appears stable. This problem occurs when your system fails to translate human-readable domain names into the numerical IP addresses that computers use to communicate. The good news is that most DNS problems are solvable with a systematic approach and a clear understanding of how the resolution process works.
Understanding How DNS Resolution Works
Before diving into fixes, it helps to understand the lookup chain that happens every time you type a URL into your browser. Your computer first checks its local hosts file, then queries a recursive resolver provided by your internet service provider. If that resolver does not have the answer cached, it traverses the root servers, top-level domain servers, and finally the authoritative nameservers for the specific domain. A break at any point in this chain will result in a failure to load the website, which is why identifying where the breakdown occurs is the first step toward resolution.
Basic Troubleshooting Steps
Start with the simplest solutions, as they often resolve the majority of cases without requiring deep technical changes. A temporary glitch in your network stack can often be cleared with a simple reboot of your device and modem. Power cycling your router refreshes the connection to your ISP and clears any corrupted local cache that might be holding onto incorrect address information.
Restart your computer, phone, or tablet.
Power cycle your router and modem by unplugging them for thirty seconds.
Ensure all cables are securely plugged into the correct ports.
Flushing the DNS Cache
Your operating system maintains a local cache of DNS records to speed up future requests. Over time, this cache can become corrupted or outdated, especially if a website has recently changed its IP address. Flushing this cache forces your device to query the internet for fresh records, which often resolves the "website not found" error.
On Windows
Open the command prompt as an administrator and run the command ipconfig /flushdns . You should see a confirmation message indicating that the resolver cache was successfully flushed.
On macOS
Depending on your version, you will typically use sudo dscacheutil -flushcache followed by sudo killall -HUP mDNSResponder to clear the cache and restart the service.
On Linux
If you are using a systemd-resolved service, the command is usually sudo systemd-resolve --flush-caches . Systems using nscd may require sudo /etc/init.d/nscd restart .
Changing Your DNS Servers
If flushing the cache does not work, the issue may lie with your ISP’s default DNS servers, which can sometimes be slow or unreliable. Switching to a public DNS provider, such as Google DNS or Cloudflare, often results in faster response times and higher reliability. This process involves changing the protocol settings in your network adapter configuration.
