How to test an Internet connection with bash?

bash connection ping
lauriys picture lauriys · May 30, 2009 · Viewed 248k times · Source

How can an internet connection be tested without pinging some website? I mean, what if there is a connection but the site is down? Is there a check for a connection with the world?

Answer

user3439968 picture user3439968 · Nov 8, 2014

Without ping

#!/bin/bash

wget -q --spider http://google.com

if [ $? -eq 0 ]; then
    echo "Online"
else
    echo "Offline"
fi

-q : Silence mode

--spider : don't get, just check page availability

$? : shell return code

0 : shell "All OK" code

Without wget

#!/bin/bash

echo -e "GET http://google.com HTTP/1.0\n\n" | nc google.com 80 > /dev/null 2>&1

if [ $? -eq 0 ]; then
    echo "Online"
else
    echo "Offline"
fi

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