Port scan a range of hosts with Netcat.

for i in {21..29}; do nc -v -n -z -w 1 192.168.0.$i 443; done
Simple one-liner for scanning a range of hosts, you can also scan a range of ports with Netcat by ex.: nc -v -n -z -w 1 21-443 Useful when Nmap is not available:) Range declaration like X..X "for i in {21..29}" is only works with bash 3.0+
Sample Output
(UNKNOWN) [] 443 (?) : Connection refused
(UNKNOWN) [] 443 (?) open
(UNKNOWN) [] 443 (?) : Connection refused
(UNKNOWN) [] 443 (?) open

By: rez0r
2009-09-25 03:31:29

What Others Think

For other Bourne family shells try for i in $(seq 21 29); do nc -v -n -z -w 1 192.168.0.$i 443; done instead.
penpen · 486 weeks and 2 days ago
On some distributions the command name is 'netcat', not 'nc', so try both.
hfs · 426 weeks and 3 days ago
one liner for powershell on windows. for ($i=1; $i++){if ($i -lt 255){.\nc.exe -v -n -z -w 1 192.168.0.$i 80;}}
tasdawg · 59 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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