"aptitude install munin"
It graphs more than I was hoping for, including: disk space, cpu load, network and even disk smart parameters.
Basic configuration of alerts is simple, edit /etc/munin/munin.conf
- Uncomment and edit a contact -line
- Determine name of plugin to configure, for example "cpu"
- it's the suffix after hyphen in the detail view URL.
- Determine name of the field to configure, for example "user"
- The fields are listed in the bottom of the detail view.
Add the warning and critical limits in [localhost.localdomain] section, for example: