It does not matter how good your security measures are, if you are the last one who realises, that you got a problem. If your users have to call you, that an important service is not working anymore, something is wrong.
To keep you informed about your network status, we use ⇒Check_MK, and other tools to monitor your environment. These products offer a big range of customization and simple alerting using mail and SMS.
Using these products for a long time in different environments, we can build you an efficient monitoring solution in a very short time period for you too.