I realize the question could be more specific: Are there any particular annoyances or great features about your monitoring solution of choice?
We have been using munin and nagios in various setups. Munin is great for the ease of plugin creation but the alerting capabilities are lacking. It also has a few fundamental flaws such as gaps in the graph when a server can not be reached.
Nagios otoh is the kitchen sink solution with extensive alerting functions, but the UI is cluttered and configuration/maintenance tend to be pretty nightmarish.
We have been using munin and nagios in various setups. Munin is great for the ease of plugin creation but the alerting capabilities are lacking. It also has a few fundamental flaws such as gaps in the graph when a server can not be reached.
Nagios otoh is the kitchen sink solution with extensive alerting functions, but the UI is cluttered and configuration/maintenance tend to be pretty nightmarish.