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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
14
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.

Notes:

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

Alternatives

There is 1 alternative - 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 282 weeks and 6 days ago

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

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

Comment by sudopeople 282 weeks and 5 days 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 260 weeks and 4 days 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 208 weeks and 4 days ago

Your point of view

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