CentOS
A Linux distribution based on derived from the sources of the Red Hat Enterprise Linux (RHEL). More info is available at www.centos.org.

Component
A software addon package for Nagios XI that extends its native capabilities. Components can add additional notification method, dashlets, menu items, or other features in a Nagios XI installation. Additional components for Nagios XI are available on Nagios Exchange.

Config Snapshots
When the configuration is applied in Nagios XI a snapshot is made of the current configuration. These configuration snapshot are stored and used to automatically roll back to the last known good configuration if a configuration cannot be applied. Additionally, the configuration snapshots can be used to store good configurations and allow users to roll back to previously know good configurations.