Every website (destination) on the internet must have an IP address. However, we humans are not very good with numbers so we have invented the Domain Name System (DNS). The primary function of the DNS is that it associates a name (domain name) with an IP address; this way, we don't need to memorize IP addresses while browsing the internet ... thank God for the DNS!
Every time you enter a domain name on your browser, the DNS translates (resolves) the domain name to its corresponding IP address. The IP address of your DNS server is stored in the file /etc/resolv.conf:
root@ubuntu-linux:~# cat /etc/resolv.conf
# Generated by NetworkManager
nameserver 142.165.200.5
I am using the DNS server 142.165.200.5, which is provided by my Internet Service Provider (ISP). You can use the nslookup command to see DNS in action. The general syntax of the nslookup command is as follows:
nslookup domain_name
The nslookup command uses DNS to obtain the IP address of a domain name. For...