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port scan using parallel

Terminal - port scan using parallel
seq 1 255 | parallel -j+0 'nc -w 1 -z -v 192.168.1.{} 80'
2011-06-11 14:40:51
User: devrick0
Functions: seq
2
port scan using parallel

It takes over 5 seconds to scan a single port on a single host using nmap

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

Alternatives

There are 6 alternatives - vote for the best!

Terminal - Alternatives

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