Clearing DNS Cache on Linux and Windows

DNS caching helps reduce lookups but sometimes you need to clear it after DNS changes, certificate updates, or to troubleshoot resolution issues.

Modern Linux with systemd-resolved

Most contemporary Linux distributions use systemd-resolved as the default DNS resolver. Flush the cache with:

sudo systemctl restart systemd-resolved

Or use the resolvectl command:

sudo resolvectl flush-caches

To verify the cache was cleared:

resolvectl statistics

Linux with NetworkManager

If your system uses NetworkManager alongside systemd-resolved:

sudo systemctl restart NetworkManager

This restarts the DNS integration but doesn’t always flush all caches. For thorough clearing, combine it with:

sudo systemctl restart systemd-resolved

Legacy: nscd (Name Service Cache Daemon)

Older distributions or systems still running nscd:

sudo systemctl restart nscd

Or via init scripts on systems without systemd:

sudo service nscd restart

Check if nscd is running:

systemctl status nscd

Checking Current DNS Configuration

View your active DNS resolver:

resolvectl status

On systems using /etc/resolv.conf:

cat /etc/resolv.conf

Note that on modern systems, /etc/resolv.conf is often a symlink to /run/systemd/resolve/resolv.conf and is managed automatically.

Flushing DNS Cache on Windows

Windows 10/11 (and Server 2016+)

Open PowerShell or Command Prompt as Administrator and run:

ipconfig /flushdns

Verify the flush succeeded:

ipconfig /displaydns

To clear DNS cache using PowerShell:

Clear-DnsClientCache

View current cached entries:

Get-DnsClientCache

Clearing Windows DNS via Group Policy

For domain-joined systems, you can also flush DNS on remote machines:

Invoke-Command -ComputerName <hostname> -ScriptBlock { Clear-DnsClientCache }

Older Windows (XP through Windows 7)

While no longer supported, the command remains:

ipconfig /flushdns

Run this from an Administrator command prompt.

Browser-Level DNS Cache

Browsers maintain their own DNS caches separate from the OS. This is useful during development or when troubleshooting specific services.

Chrome/Chromium

Navigate to:

chrome://net-internals/#dns

Click “Clear host cache” to flush Chrome’s DNS cache. You can also view recent DNS queries on this page.

Firefox

Firefox doesn’t expose a direct DNS cache flush in the UI. Instead, restart the browser or access about:networking#dns to view DNS information. For debugging, use:

about:config

Search for network.dnsCacheExpiration and reduce the value (in seconds) to force faster cache expiration.

Edge

Navigate to:

edge://net-internals/#dns

Same functionality as Chrome since Edge uses Chromium.

Troubleshooting DNS Issues

After flushing caches, verify DNS resolution:

# Test DNS resolution
nslookup example.com
dig example.com
getent hosts example.com

On Windows:

nslookup example.com

If issues persist after flushing, check that your DNS servers are correctly configured:

resolvectl query example.com

This shows which resolver handled the request and helps identify configuration problems.

2026 Best Practices and Advanced Techniques

For Clearing DNS Cache on Linux and Windows, understanding both the fundamentals and modern practices ensures you can work efficiently and avoid common pitfalls. This guide extends the core article with practical advice for 2026 workflows.

Troubleshooting and Debugging

When issues arise, a systematic approach saves time. Start by checking logs for error messages or warnings. Test individual components in isolation before integrating them. Use verbose modes and debug flags to gather more information when standard output is not enough to diagnose the problem.

Performance Optimization

• Monitor system resources to identify bottlenecks
• Use caching strategies to reduce redundant computation
• Keep software updated for security patches and performance improvements
• Profile code before applying optimizations
• Use connection pooling and keep-alive for network operations

Security Considerations

Security should be built into workflows from the start. Use strong authentication methods, encrypt sensitive data in transit, and follow the principle of least privilege for access controls. Regular security audits and penetration testing help maintain system integrity.

Related Tools and Commands

These complementary tools expand your capabilities:

• Monitoring: top, htop, iotop, vmstat for system resources
• Networking: ping, traceroute, ss, tcpdump for connectivity
• Files: find, locate, fd for searching; rsync for syncing
• Logs: journalctl, dmesg, tail -f for real-time monitoring
• Testing: curl for HTTP requests, nc for ports, openssl for crypto

Integration with Modern Workflows

Consider automation and containerization for consistency across environments. Infrastructure as code tools enable reproducible deployments. CI/CD pipelines automate testing and deployment, reducing human error and speeding up delivery cycles.

Quick Reference

This extended guide covers the topic beyond the original article scope. For specialized needs, refer to official documentation or community resources. Practice in test environments before production deployment.