Check if a remote port is up using dnstools.com (i.e. from behind a firewall/proxy)

cpo(){ [[ $# -lt 2 ]] && echo 'need IP and port' && return 2; [[ `wget -q "http://dnstools.com/?count=3&checkp=on&portNum=$2&target=$1&submit=Go\!" -O - |grep -ic "Connected successfully to port $2"` -gt 0 ]] && return 0 || return 1; }
Shell function; returns 0 if the port is up, 1 otherwise (check $? after executing). First parameter: IP address/hostname Second parameter: port number There is no error checking for the input parameters.

1
By: marek158
2011-09-26 12:11:51

What Others Think

Why not use a simple OPEN/CLOSED instead of using return? cpo(){ [[ $# -lt 2 ]] && echo 'need IP and port' && return 2; [[ `wget -q "http://dnstools.com/?count=3&checkp=on&portNum=$2&target=$1&submit=Go\!" -O - |grep -ic "Connected successfully to port $2"` -gt 0 ]] && echo OPEN || echo CLOSED; }
kadu · 353 weeks and 6 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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