What Is DNS Propagation?
DNS propagation is the time it takes for changes to your domain's DNS settings to spread across all DNS servers worldwide. When you update nameservers, add DNS records, or make other changes, these updates do not take effect instantly.
How DNS Propagation Works
The internet relies on a network of DNS servers that cache domain information. When you make a change:
- The update is applied to your authoritative nameserver (e.g., SillyHost's nameservers).
- Other DNS servers around the world still have the old cached version.
- As their cached records expire (based on the TTL value), they query the authoritative server for the updated information.
- Gradually, all DNS servers worldwide receive the new data.
Typical Propagation Times
- A, AAAA, CNAME records: Usually 1 to 4 hours if the TTL was set to a low value. Can take up to 24 hours with higher TTL values.
- MX records: Typically 1 to 12 hours.
- Nameserver changes: 24 to 48 hours in the worst case, though most users see changes within 4 to 6 hours.
- TXT records: Usually 1 to 4 hours.
How to Speed Up Propagation
- Lower the TTL before making changes. Set it to 300 seconds (5 minutes) at least 24 hours before the planned change.
- After the change has propagated, you can raise the TTL back to a higher value like 3600 (1 hour) or 86400 (24 hours).
Checking Propagation Status
Use online tools such as whatsmydns.net or dnschecker.org to check whether your DNS changes have propagated to servers in different regions around the world.
During propagation, some visitors may see your old site while others see the new one. This is normal and temporary.