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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

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Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

beep when a server goes offline

Terminal - beep when a server goes offline
while true; do [ "$(ping -c1W1w1 server-or-ip.com | awk '/received/ {print $4}')" != 1 ] && beep; sleep 1; done
2009-03-31 20:47:56
User: sudopeople
Functions: sleep
beep when a server goes offline

pings a server once per second, and beeps when the server is unreachable.

Basically the opposite of:

ping -a server-or-ip.com

which would beep when a server IS reachable.

You could also substitute beep with any command, which makes this a powerful alternative to ping -a:

while true; do [ "$(ping -c1W1w1 server-or-ip.com 2>/dev/null | awk '/received/ {print $4}')" = 1 ] && date || echo 'server is down!'; sleep 1; done

which would output the date and time every sec until the ping failed, in which case it would echo.


Requires beep package.

May need to run as root (beep uses the system speaker)

Tested on Ubuntu which doesn't have beep out of the box...

sudo apt-get install beep


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

I think you can get rid of a bit of complexity (and the awk) out of this by simply using the bash OR operator, instead of the contitional test used now. Also, by using the bash block operators, { }, you can jam multiple commands after the OR expressions.

while true; do ping -c1W1w1 server-or-ip.com 2>/dev/null || { echo Server down; beep; } ; sleep 1; done

And another slight edit to do branching:

while true; do ping -c1W1w1 google.com &>/dev/null && { echo Up;} || { echo Down; beep; } ; sleep 1; done

Runs one block if the server is up, and another if it's down.

Hope this helps!

Comment by clockworkavian 394 weeks and 2 days ago

@clockworkavian: thanks for reminding me about the braces :)

and the optomizations make this much easier to read, ty ty!

Comment by sudopeople 394 weeks and 1 day ago

Great command, nice. I am a mac user so, beep isn't installed and the ping command has no -w option. I played around and made this mac version. It is just a small modification to clockworkavian's way with using the bash OR operator, cleaning up ping and using the mac speech synthesis to alert you what is going on.

while true; do ping -c1 -W1 google.com &>/dev/null && { say "up";} || { say "down"; } ; sleep 1; done

if the "up" goes on your nerves after sometime you could just take it out.

Comment by netsaint 372 weeks ago

Mac users can just use the -A option for ping which will beep when no reply is received.

you can also use -a if you want an "Everything is OK" alarm.

Comment by LIV2 320 weeks ago

Your point of view

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