icinga2

Check configuration

$ icinga2 daemon -C

$ sudo systemctl start icinga2

$ sudo systemctl reload icinga2

$ icinga2 feature list

$ sudo icinga2 feature enable [api]

$ icinga2 object list --type Host

icinga2 command [options]

Icinga 2 is a monitoring system that checks availability of hosts and services. It supports distributed monitoring, advanced configurations, and integrates with various backends.
Icinga 2 uses a domain-specific language (DSL) for configuration, supporting templates, apply rules, and runtime modifications through its API.

daemon [-C]

Run daemon (or check config with -C).

Manage features (list, enable, disable).

Object management (list).

Node/cluster management.

PKI/certificate management.

Open debug console.

Show version.

- Host and service monitoring
- Distributed/clustered setup
- REST API
- Graphite/InfluxDB integration
- Notification system
- Performance data

Configuration syntax differs from Icinga 1/Nagios. Cluster setup requires PKI. Large installations need tuning. Web interface (Icinga Web 2) installed separately.

Icinga was forked from Nagios in 2009 due to disagreements about project governance. Icinga 2, released in 2014, was a complete rewrite with modern architecture and new configuration language.

nagios(8), prometheus(1), zabbix(1)