How to Check DNS Propagation Properly

DNS propagation is usually DNS caching. When you change a record, the authoritative nameserver may update quickly, but resolvers around the internet can keep the old answer until its TTL expires.

To check DNS properly, do not rely on one browser tab or one online checker. Check the authoritative nameserver first, then compare a few public resolvers, then confirm the actual service you are testing.

Before You Start

• Know the exact record name, such as example.co.uk, www.example.co.uk, or mail.example.co.uk.
• Know the record type: A, AAAA, CNAME, MX, TXT, or NS.
• Know the value you expect to see.
• Check the TTL that was set before the change, because that controls how long old answers may be cached.

Step 1: Check the Authoritative Nameserver

The authoritative nameserver is the source of truth for the domain. If it still shows the old value, the change has not been applied correctly at the DNS provider.

On macOS or Linux, run:

dig NS example.co.uk

Then query one of the returned nameservers directly:

dig @ns1.example-dns-provider.co.uk example.co.uk A

For a www record, query the full hostname:

dig @ns1.example-dns-provider.co.uk www.example.co.uk A

If the authoritative nameserver returns the expected value, the DNS provider has the correct record. The remaining delay is likely resolver caching.

Step 2: Check Public Resolvers

Now compare a few public resolvers. This shows whether common recursive DNS services have picked up the change.

dig @1.1.1.1 example.co.uk A
dig @8.8.8.8 example.co.uk A
dig @9.9.9.9 example.co.uk A

If some resolvers show the new value and others show the old value, the change is in progress. Wait for the old TTL to expire before assuming something is broken.

Step 3: Check the Right Record Type

Make sure you are checking the record that actually controls the service:

• Website: usually A, AAAA, or CNAME.
• Email delivery: MX, plus related TXT records for SPF, DKIM, and DMARC.
• Domain verification: often a TXT or CNAME record.
• Nameserver move: NS records at the registrar and sometimes glue records.

Step 4: Check IPv6 as Well as IPv4

If a site has an AAAA record, some visitors may reach the IPv6 address instead of the IPv4 address. A correct A record does not fix a wrong AAAA record.

dig example.co.uk A
dig example.co.uk AAAA

If you do not intentionally use IPv6, remove stale AAAA records instead of leaving them pointed at an old server.

Step 5: Check the Website Separately

DNS can be correct while the website still fails. After the DNS answer is right, check the actual HTTP response:

curl -I https://example.co.uk

Look for the status code, redirects, and SSL behaviour. If the domain resolves to the new server but the site shows the wrong content, check virtual host configuration, document root, cache, and SSL setup.

Step 6: Check Email Separately

Email uses MX records, not the website's A record. If email stops working after a website move, check that the MX records still point to the mail provider you intended to use.

dig example.co.uk MX
dig example.co.uk TXT

If the website is moving but email is staying elsewhere, do not replace the whole DNS zone blindly. Keep existing MX, SPF, DKIM, and DMARC records unless you are deliberately moving email too.

Common Mistakes

• Checking example.co.uk when the changed record was www.example.co.uk.
• Forgetting that A and AAAA records can point to different servers.
• Changing nameservers and individual DNS records at the wrong provider.
• Expecting every resolver to update before the previous TTL expires.
• Clearing browser cache when the problem is DNS resolver cache.

How Long Should DNS Propagation Take?

If the authoritative nameserver is correct, many changes appear quickly. However, resolvers that cached the old record can keep serving it until the old TTL expires. If the previous TTL was 3600 seconds, allow at least an hour. If it was 86400 seconds, some users may see the old answer for much longer.

TekLan Hosting Notes

If your domain and hosting are both managed with TekLan, many standard DNS records are handled for you. If you are moving only the website, tell us whether email should stay where it is so MX and TXT records are preserved.

Related guides: Setting Up DNS Records, Pointing Your Domain to Your Hosting, and What DNS Propagation Actually Means.