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

Terminal - 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; }
2011-09-26 12:11:51
User: marek158
Functions: echo grep return
1
Check if a remote port is up using dnstools.com (i.e. from behind a firewall/proxy)

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.

Alternatives

There are 4 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

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; }
Comment by kadu 269 weeks and 5 days ago

Your point of view

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