Domain Verification & DNS Propagation
What to expect when verifying your CNAME, how DNS propagation works, and what to do if verification fails.
How Domain Verification Works
When you click Verify Domain in SMLLR, our system performs a DNS lookup on your subdomain and checks whether it has a CNAME record pointing to cname.smllr.app.
If the CNAME is found and correct, verification succeeds instantly and the domain status changes to Verified & Active.
If the CNAME is not yet visible, verification fails with an error. This does not mean anything is wrong — the DNS record may simply not have propagated yet.
DNS Propagation — What It Is and How Long It Takes
When you add a DNS record, the change must spread across DNS servers around the world. This process is called DNS propagation.
Typical propagation times:
- Most DNS providers: 15–60 minutes
- Cloudflare: Usually under 5 minutes
- Some registrars: Up to 24 hours in rare cases
During propagation, some DNS servers have the new record and others do not. This is normal — there is nothing you can do to speed it up other than waiting.
After adding the CNAME, wait at least 15–30 minutes before clicking Verify Domain. If it fails, wait another 30 minutes and try again.
How to Check if Your CNAME is Live
DNS lookup tools query public DNS servers. Even if your tool shows the CNAME is live, SMLLR's verification server may query a different DNS server that hasn't propagated yet. If SMLLR verification still fails, wait another 15 minutes and try again.
Use a DNS lookup tool
Open any free DNS CNAME lookup tool (search 'CNAME lookup' in Google).
Enter your subdomain
Enter your full subdomain — e.g. go.yourbrand.com.
Check the result
The result should show a CNAME pointing to cname.smllr.app. If it shows nothing, or shows a different value, the CNAME is either not set or not yet propagated.
What to Do if Verification Keeps Failing
Double-check the CNAME value — confirm you entered exactly
cname.smllr.appas the value/target (no extra characters, no trailing dot required)Check the Name/Host field — it should be just the subdomain prefix (e.g.
go), not the full subdomain (go.yourbrand.com). Some providers auto-append your domain.Check for conflicting records — if your subdomain already has an A record or another CNAME, the new CNAME may be blocked. Remove conflicting records first.
Check Cloudflare proxy — if using Cloudflare, ensure the CNAME record is set to DNS Only (grey cloud icon), not Proxied (orange cloud). Proxied mode will break SMLLR's verification.
Wait 24 hours — if it has been less than 24 hours since you added the record, give it more time.
Contact support — if it has been more than 24 hours and verification still fails after the above checks, email [email protected] with your subdomain and a screenshot of your DNS settings.
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