Use ping to test if a server is up

if [ "$(ping -q -c1 google.com)" ];then wget -mnd -q http://www.google.com/intl/en_ALL/images/logo.gif ;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.

-1
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 google.com)" ] && wget ... 'if' works by using the '[' (test) command, but you can use it directly.
flatcap · 443 weeks and 6 days ago
Alternatively (not as pretty): ping -c1 google.com > /dev/null && wget ...
flatcap · 443 weeks and 6 days 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 · 443 weeks and 6 days ago
I don't have the means to test this example at the moment, but I believe it should work. curl -Is google.com 2>&1 | grep -q "200 OK" && wget ...
eightmillion · 443 weeks and 6 days ago
Great alternatives, I'll have to give these a try!
alf · 443 weeks and 6 days ago
'if' expects a command. '[' is actually a program, not part of the shell. So you can actually just do if ping -q -c1 google.com; then ...
recursiverse · 443 weeks and 5 days ago
No need for the 'then' or even an 'else', just use && or || e.g.: ping -c1 host.com > /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 · 415 weeks and 4 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?

You must be signed in to comment.

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands



Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: