Use ping to test if a server is up

if [ "$(ping -q -c1" ];then wget -mnd -q ;fi
Bash scrip to test if a server is up, you can use this before wget'ing a file to make sure a blank one isn't downloaded.

By: alf
2010-03-23 04:15:03

What Others Think

If you're not going to have an "else" clause, you can shorten that to: [ "$(ping -q -c1" ] && wget ... 'if' works by using the '[' (test) command, but you can use it directly.
flatcap · 605 weeks and 1 day ago
Alternatively (not as pretty): ping -c1 > /dev/null && wget ...
flatcap · 605 weeks and 1 day ago
Wouldn't it be better to use curl -I to check the headers for a 200 OK? Just because a machine is responding to pings, that doesn't mean that the webserver is up.
eightmillion · 605 weeks ago
I don't have the means to test this example at the moment, but I believe it should work. curl -Is 2>&1 | grep -q "200 OK" && wget ...
eightmillion · 605 weeks ago
Great alternatives, I'll have to give these a try!
alf · 605 weeks ago
'if' expects a command. '[' is actually a program, not part of the shell. So you can actually just do if ping -q -c1; then ...
recursiverse · 605 weeks ago
No need for the 'then' or even an 'else', just use && or || e.g.: ping -c1 > /dev/null && echo "YES" || echo "NO" This is the equivalent of: if ping -c1 host .com > /dev/null then echo "YES" else echo "NO" fi
finkployd · 576 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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