Fix Website Not Loading After DNS Change

Understanding DNS Propagation

DNS changes take time to spread globally (up to 48 hours).

Check Propagation Status

# Use online tools
https://dnschecker.org
https://www.whatsmydns.net

If some locations show old IP, propagation is still in progress.

Fix 1: Check TTL Before Changing

Reduce TTL to 300 seconds (5 minutes) 24 hours before planned changes.

Fix 2: Flush Local DNS Cache

Force your computer to refresh:

# Windows
ipconfig /flushdns

# macOS
sudo dscacheutil -flushcache

# Linux
sudo systemd-resolve --flush-caches

Fix 3: Use Different DNS Resolver

ISP DNS caches longer. Temporarily use Google/Cloudflare:

# Test with dig
dig @8.8.8.8 yourdomain.com

Fix 4: Check Hosts File Override

Old hosts entry may override DNS:

# Linux/macOS
cat /etc/hosts

# Windows
type C:WindowsSystem32driversetchosts

Remove any entries for your domain.

Fix 5: Verify New Server is Ready

Before DNS change, ensure new server is configured and serving content:

curl -I http://NEW_SERVER_IP
# Or test with host header
curl -H "Host: yourdomain.com" http://NEW_SERVER_IP

Fix 6: Use Incognito Mode

Browser caches DNS aggressively. Try private browsing window.

Fix 7: Check SSL Certificate

If moving domains between servers:

# New server needs proper SSL for domain
sudo certbot --nginx -d yourdomain.com