WhoisUP – Is your host up or down?

During last months, I have not written tutorial about Cisco technology because I have dedicated my free time to write my personal script to monitor hosts, router and so on. Why write a new script and not use a pre-existent script/software? The reasons are different, but in particular three: Surfing the web, I have found software that check hosts with a minute delay (they use crontab…), but in my case I want to check hosts continuously; other software can check hosts continually, but they are too complex for my purpose and they have features don’t needed in my case. They can be too expensive. The second reason [...]