DNS CNAME Record Lookup

What is DNS ?

DNS (Domain Name System) is a service that translates domain names into IP addresses. Users can easily remember domain names, but computers only understand IP addresses that’s why we need DNS. For example, without this service, you have to type '185.60.216.35' in your browser instead of www.facebook.com to access Facebook. IP - Domain mappings are kept on DNS servers. You can query those matches on s4e.io

There are two types of IP addresses IPv4, and IPv6. IPv4 address looks like these:

            8.8.8.8
            127.0.0.1
            255.255.255.255

IPv6 addressed looks like these (all of them are the same IP):

            ::ffff:808:808
            0:0:0:0:0:ffff:0808:0808
            0000:0000:0000:0000:0000:ffff:0808:0808

What is DNS CNAME RECORD?

CNAME (Canonical Name) is a type of DNS record that is used as an alias for another domain. Let's give a real-life example. You bought a domain such as s4e.io then you offer an online email service. To do that you've created a new subdomain such as email.s4e.io. However, you found out that some email clients use the webmail subdomain as default. In that case, you can use a CNAME record to map webmail.s4e.io to email.s4e.io. CNAME records must point to a domain name, not an IP address.

Also, another example of using CNAME records is using multiple ports of the same IP addresses. You can use ftp.s4e.io (21), tomcat.s4e.io (8080), apache.s4e.io (80,443) on the same IP addresses. All of them can point to s4e.io in the CNAME records. With that, when you move your server to another IP address you have to change s4e.io's A record only.

How to Test DNS CNAME Record?

Simple. Write your domain on the form at the top of the page to check cname records, that's all. Using S4E’s free cname lookup, you can get cname records and find all cname records for a domain as well as cname record check. Generally, people use CNAME to points to another subdomain or main domain. You can use DNS CNAME lookup tool to get them.

Or if you are using a Linux or an OS X operating system, open the terminal and type dig -t cname yourdomain.com. If your domain has a valid cname record, it would look like that:

          dig -t cname s4e.io
          ;; ANSWER SECTION:
          www.s4e.io.	168	IN	CNAME	s4e.io.

If you are using Windows open PowerShell and type Resolve-DnsName -Name yourdomain.com -Type cname.