The most efficient way to check DNS records in Linux is using dig command.
This command will send the DNS query to the name servers listed in the resolver(/etc/resolv.conf). It allows you to query information about various DNS records, including A record, MX record CNAME record etc.
The following commands can be used to check DNS records in Linux.
- dig dnsrecords.com
- dig @126.96.36.199 dnsrecords.com
- dig dnsrecords.com ANY
- dig dnsrecords.com +short
- dig dnsrecords.com +trace
Table of Contents
How to use dig command
We can use dig name + record type + @dns server to query the DNS info from a DNS server. By default, dig performs a lookup for an A record if no type argument is specified.
dig @server name type
- server – the IP address or hostname of the name server to query. It is optional and if we don’t provide a server argument then dig uses the name server listed in /etc/resolv.conf.
- name – the name of the resource record that is to be looked up.
- record type – the type of query requested by dig. For example, it can be an A record, MX record, SOA record or any other types.
Check DNS A record with dig command
The A stands for address and this is the most fundamental type of DNS record.
A record is used to point a domain or subdomain to an IP address. We can use this command to query A record for a domain name.
$ dig www.howtouselinux.com
www.howtouselinux.com. 0 IN A 188.8.131.52
Query DNS PTR record with dig command
A PTR record is well-known as the reverse version of an A record. We can get the PTR record with this command.
This is the PTR record for IP address 184.108.40.206.
$ dig -x 220.127.116.11
Query DNS MX record with dig command
A DNS ‘mail exchange’ (MX) record directs email to a mail server. This record can tell us the email server for a domain name. With the following command, we can get the MX record for google.com.
$ dig google.com mx
google.com. 0 IN MX 10 aspmx.l.google.com.
google.com. 0 IN MX 20 alt1.aspmx.l.google.com.
google.com. 0 IN MX 50 alt4.aspmx.l.google.com.
google.com. 0 IN MX 30 alt2.aspmx.l.google.com.
google.com. 0 IN MX 40 alt3.aspmx.l.google.com.
Get DNS records Against a specific DNS server with dig command
Many DNS servers are around the world. To specify a name server against which the query will be executed, use the @ (at) symbol followed by the name server IP address or hostname.
$ dig www.howtouselinux.com @18.104.22.168
www.howtouselinux.com. 5 IN A 22.214.171.124
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