Check the DNS entries of the domain or subdomain
Provide a web address and check DNS entries for the provided host name.
DNS Servers
There are more than 1.5 billion websites on the Internet today, all hosted on different global servers globally. While some have pretty straightforward domain names, some make use of subdomains to show country or region-specific information to users. Now while a user may be able to bookmark a website to easily access it every time, have you ever wondered how a web browser knows which webpage of which website to open for you when you type a URL?
A DNS Server is how!
Think of a DNS server as a yellow-page directory. It’s what your web browser uses to match a website’s domain name with the correct IP address. These magic servers let your computer find the exact website you’re looking for and load it appropriately.
What are DNS servers?
DNS (Domain Name System) servers are computer servers that contain databases of public IP addresses and their corresponding domain names. When a user enters a URL in his web browser, the browser sends a request to the local DNS server which then conducts a search to locate the IP address that he wishes to visit. The entire process of retrieving the desired information is carried out with the help of several intermediate servers (DNS resolver, root server, TLD server, and authoritative server), with each one translating a different part of the domain name you had originally entered in your web browser. When all these servers finish working and send the information back to the requesting DNS server, the information is sent back to the user’s web browser and is displayed to him.
What are some common DNS records?
Each DNS record represents an individual entry matching an IP address to a domain name. The different types of DNS records are:
- Address mapping (A) records: The most common kind, “A” records are used to map domain names to IPv4 addresses.
- Mail exchanger (MX) records: The domain names of mail servers responsible for receiving emails on behalf of a domain are stored in mail exchanger (MX) records.
- Canonical name (CNAME) records: This record serves as an alias, mapping one name to the next. It’s also used to eliminate duplicate domain name configurations.
- AAAA records: The IPv6 equivalent of an A record is an AAAA record, which maps a domain name to an IPv6 address.
- Pointer (PTR) records: An A or AAAA record is the opposite of a pointer (PTR) record. PTR records translate IPv4 and IPv6 addresses into domain names. PTR records are used in reverse DNS lookups.
- Name Server (NS) records: The NS record specifies that a DNS Region, such as “example.com,” has been assigned to a particular Authoritative Name Server, and it also contains the name server’s address.
- Text (TXT) records: TXT Records generally contain machine-readable information like encryption, sender policy system, DKIM, DMARC, and so on.
- Start of Authority (SOA) records: These records contain valuable information about the zone, such as the zone’s primary authoritative name server and the email address of the zone’s administrator.
How to check the DNS records for a specific domain?
Using a terminal and the command nslookup is the most effective way to search a domain’s DNS records. On almost all operating systems, this command works perfectly and displays all DNS records for the domain.
To show how to use the command, here’s a sample nslookup command for each record type.
Note: We’ll be using the domain name xxxyyy.com, which should be replaced by the one you’re going to work with.
- Lookup A record: nslookup -type=A xxxyyy.com
- Lookup NS record: nslookup -type=NS xxxyyy.com
- Lookup MX record: nslookup -type=MX xxxyyy.com
- Lookup CNAME record: nslookup -type=CNAME xxxyyy.com
If using the command line seems too complicated, you can search DNS records for a domain using one of the many trusted online resources available. The best three such resources are:
- DNSRecords – Allows you to access the domain name and receive all of the domain DNS records.
- DNSChecker.org – Displays all DNS records for a domain as well as how those records are propagated across the internet.
- LeafDNS – Displays DNS records for a domain and also displays alerts/failures. The tool determines if your DNS records are right or not. It comes in handy when creating custom name servers for a domain.
Note: If none of the above-mentioned methods work, please use the tool above to check the DNS records of your domain.
