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Now the registrar may not be who actually controls your Domain Name’s records, as the Nameservers (the records below)dictate who actually controls your DNS settings which include your A record, CNAME records and records like eMail (MX records) and others including TXT and SPF records.
If the top nameserver is not your registrar’s nameserver, and or this may manifest itself in the event that when you make changes to the domain name’s DNS records (DNS Settings) nothing actually changes when you use DNS Lookup to check the A record or CNAME record, then you must then check who the Nameservers are managed by, and therefore where your DNS records are being managed from.
To do that, you can either already see that from the WHOIS record using MXtoolbox, or you can check without WhoIS info and then instead use MX Toolbox’s SuperTool and click the DNS Check orange button.
https://mxtoolbox.com/SuperTool.aspx
Enter the root domain and select DNS Check from the Orange dropdown button
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In this unusual example above, you can see the Nameserver(s) are Godaddy’s but the Domain Name is registered with 123-reg. So that means the Website records and email records are being managed from Godaddy as the DNS provider for this Domain name. This can be the case when email companies get involved in domain name management as they can switch your records to their DNS and Email management service provider e.g. Siteground or another company like Godaddy.
So that deals with the registrar and nameservers, so now how do you check the status of your A records and CNAME records for your domain name and more importantly your www.domainname.XXX. The easiest way is to use MXTOOLBOX:
https://mxtoolbox.com/DnsLookup.aspx
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