time (nmap -p 80 192.168.1.1 &> /dev/null)
real 0m5.109s
user 0m0.102s
sys 0m0.004s
It took netcat about 2.5 minutes to scan port 80 on the class C
time (for NUM in {1..255} ; do nc -w 1 -z -v 192.168.1.${NUM} 80 ; done &> /dev/null)
real 2m28.651s
user 0m0.136s
sys 0m0.341s
Using parallel, I am able to scan port 80 on the entire class C in under 2 seconds
time (seq 1 255 | parallel -j255 'nc -w 1 -z -v 192.168.1.{} 80' &> /dev/null)
real 0m1.957s
user 0m0.457s
sys 0m0.994s
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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