Not all program updates go well. There will be occasions when a program update may have lead to an unstable system due to hardware compatibility issues. For this or whatever the reason, if you want your previous version program back, you need to know how to downgrade the applications.
Prometheus is an open-source toolkit initially built at SoundCloud for monitoring and alerting. It collects metrics from monitored targets by scrapping HTTP endpoints on those targets.
Are you looking for an IT monitoring solution that free and open source? Check_MK Server is one of the best monitoring system out there that was started originally as an extension to the Nagios monitoring system. Here we are going to install and configure the CRE version (Check_MK Raw Edition) which is open-source and 100% free.