I recently had the need to set-up a regular ping of a server with an email alert if the server went down. To do this I wrote a simple ping monitor script in bash.
The script can be downloaded from the following:
From a terminal you can do
sudo wget http://blogs.barlow.uk.net/content/downloads/pingmonitor.sh
sudo chmod +x ./pingmonitor.sh
You will need to change SERVER IP with the ip address of the server, or servers you would like to monitor. You will also have to change YOUREMAIL ADDRESS with the email address you would like to receive these emails.