In some cases you need the servers IP-address, but you only have it's domain e.g. example.com. There are many different ways to retrieve the servers IP-address from its domain.
One way of getting the IP-address by its domain, is by using the default shell command ping. Using the command ping <domain> will return the servers IP-address.
Example of the output from the ping command using the domain example.com.
$ ping example.com
Pinging example.com [93.184.216.34] with 32 bytes of data:
Reply from 93.184.216.34: bytes=32 time=95ms TTL=55
Reply from 93.184.216.34: bytes=32 time=92ms TTL=55
Reply from 93.184.216.34: bytes=32 time=93ms TTL=55
Reply from 93.184.216.34: bytes=32 time=93ms TTL=55
Ping statistics for 93.184.216.34:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 92ms, Maximum = 95ms, Average = 93ms
$
In the square brackets you can see the servers IP-address.
Read about how to bypass IP protection at: SRV Records