To scan a single machine in your network using nmap, all you need is the IP address of the machine, like this.
Or hostname, like this.
If the target machine does not exist, is down, or is configured to block ICMP packets, something like this should be returned.
Starting Nmap 6.40 ( http://nmap.org ) at 2020-08-30 10:56 CDT Note: Host seems down. If it is really up, but blocking our ping probes, try -Pn Nmap done: 1 IP address (0 hosts up) scanned in 3.06 seconds
If the machine is up and is not blocking ICMP packets, something like this should be returned.
Starting Nmap 6.40 ( http://nmap.org ) at 2020-08-30 10:50 CDT Nmap scan report for 192.168.0.22 Host is up (0.00027s latency). Not shown: 994 closed ports PORT STATE SERVICE 22/tcp open ssh 80/tcp open http 139/tcp open netbios-ssn 443/tcp open https 445/tcp open microsoft-ds 3306/tcp open mysql Nmap done: 1 IP address (1 host up) scanned in 0.11 seconds
Scan a range of IP addresses
Here is how you would scan a range of IP addresses.
Scan every IP address in a subnet
Here is how you would scan every IP address in a subnet.
Note - This command may take a long time to complete, especially if your subnet contains a large number of hosts
For this reason, it's helpful to include the --status-every xx option
nmap 192.168.0.0/24 --stats-every 5s