I recently wanted to check which servers on a large sub-net was listening on port 22/tcp.

Now nmap is obviously the tool to use, but the output was very long, and not all that clear. Here is a quick one liner I did, and maybe some one else can use this as well.

$ nmap -P0 -sT -p22 10.0.102.0/23 | perl -e 'while(<>){ chomp; push( @l, $_ ); } $lc = -1; foreach $t ( @l ) { $lc++; if( $t =~ /Interesting ports on (\d+\.\d+\.\d+\.\d+)/ ) { $ip = $1; $nlc = $lc + 2; if( $l[$nlc] =~ /open/ ) { print "IP: $ip\t\t$l[$nlc]\n"; } } }'
IP: 10.0.102.3                22/tcp open  ssh
IP: 10.0.102.4                22/tcp open  ssh
IP: 10.0.102.5                22/tcp open  ssh
IP: 10.0.102.54               22/tcp open  ssh
IP: 10.0.102.57               22/tcp open  ssh
IP: 10.0.102.58               22/tcp open  ssh
IP: 10.0.102.59               22/tcp open  ssh
IP: 10.0.102.69               22/tcp open  ssh
IP: 10.0.102.250              22/tcp open  ssh
IP: 10.0.102.251              22/tcp open  ssh
IP: 10.0.103.54               22/tcp open  ssh
IP: 10.0.103.57               22/tcp open  ssh
IP: 10.0.103.58               22/tcp open  ssh
IP: 10.0.103.59               22/tcp open  ssh
IP: 10.0.103.69               22/tcp open  ssh