Identity

Unit: netdata.service
Config: /etc/netdata/netdata.conf, override dir /etc/netdata/
Plugin dirs: /usr/libexec/netdata/plugins.d/ (internal), /etc/netdata/python.d/ (Python collectors), /etc/netdata/go.d/ (Go collectors)
Logs: journalctl -u netdata, /var/log/netdata/error.log, /var/log/netdata/access.log, /var/log/netdata/debug.log
User: netdata (runs as its own system user)
Web dashboard: http://localhost:19999
Install (one-liner): wget -O /tmp/netdata-kickstart.sh https://get.netdata.cloud/kickstart.sh && sh /tmp/netdata-kickstart.sh
Distro install: apt install netdata / dnf install netdata (older package versions — prefer kickstart for current release)

Key Operations

Operation	Command
Status	`sudo systemctl status netdata`
Check dashboard	`curl -s http://localhost:19999/api/v1/info \| python3 -m json.tool`
Simple dashboard ping	`curl -sI http://localhost:19999`
Check claimed status (Cloud)	`sudo netdata-claim.sh -status` or `cat /var/lib/netdata/cloud.d/claimed_id`
Reload config (no restart)	`sudo kill -USR1 $(pidof netdata)` — reloads health alarms; full config requires restart
Restart	`sudo systemctl restart netdata`
netdata-cli	`sudo netdatacli help` — send commands to running agent (reload health, pause, resume)
Reload health alarms only	`sudo netdatacli reload-health`
Check installed plugins	`ls /usr/libexec/netdata/plugins.d/`
List detected charts	`curl -s http://localhost:19999/api/v1/charts \| python3 -c "import sys,json; d=json.load(sys.stdin); [print(k) for k in d['charts']]"`
View error log	`sudo tail -f /var/log/netdata/error.log`
Debug mode (foreground)	`sudo netdata -D` — runs in foreground, verbose output to terminal
Health alarm status	`curl -s http://localhost:19999/api/v1/alarms \| python3 -m json.tool`
Silence an alarm	`sudo netdatacli silence-all-alarms` or per-chart: `sudo netdatacli silence-alarm <alarm_id>`

19999/tcp (HTTP dashboard and API)
Verify: ss -tlnp | grep netdata
Firewall (local dashboard only — do not expose publicly without auth): sudo ufw allow from <your-ip> to any port 19999
Firewall (block public access): sudo ufw deny 19999

systemctl is-active netdata → active
curl -sf http://localhost:19999/api/v1/info > /dev/null && echo OK → OK
curl -s http://localhost:19999/api/v1/alarms | python3 -c "import sys,json; d=json.load(sys.stdin); print(d.get('status', 'unknown'))" → alarm summary with counts

Symptom	Likely cause	Check/Fix
Port 19999 unreachable from outside	Firewall blocking or Netdata bound to `localhost` only	Check `bind to = 0.0.0.0` in `[web]` section; check `ufw status`
Plugin not auto-detecting a service	Plugin runs as `netdata` user without permissions to read stats	Check plugin logs in `/var/log/netdata/error.log`; add `netdata` user to the relevant group (e.g., `sudo usermod -aG docker netdata`)
Netdata Cloud agent connection failing	Wrong claim token, proxy blocking outbound, or clock skew	Verify token via `netdata-claim.sh -status`; check `/var/log/netdata/error.log` for TLS errors; confirm `chronyc tracking` shows <1s offset
Memory usage high	Too many enabled collectors or long retention history	Disable unused plugins in `[plugins]` section; reduce `history` in `[global]`; switch `memory mode = dbengine` and tune `page cache size`
Alarm triggering incorrectly	Default thresholds tuned for generic workloads	Override alarm in `/etc/netdata/health.d/<alarm>.conf`; use `to: silent` to suppress; tune `warn` and `crit` expressions
Python plugin fails silently	Missing Python dependency for that collector	Run manually: `sudo -u netdata /usr/libexec/netdata/plugins.d/python.d.plugin <module> debug trace`; install missing dep
`netdata-claim.sh` not found	Older package install missing Cloud tools	Re-run kickstart: `sh /tmp/netdata-kickstart.sh --claim-token <token> --claim-rooms <room>`

Zero-config is genuine but can over-collect: Netdata auto-detects hundreds of metrics on start. On small servers, disable plugin categories you don't need ([plugins] section) — the CPU and memory savings are significant.
1-second granularity costs more RAM and disk than other tools: The default dbengine mode writes to disk, but RAM pressure from the page cache still grows with metric count. Monitor with ps aux | grep netdata and tune page cache size in [global].
Cloud sync is optional: The agent works entirely standalone — local dashboard, alarms, and data retention all function without a Netdata Cloud account. Claiming to Cloud adds centralized visibility and alert routing but is not required.
Plugin detection depends on the target process running at Netdata startup: If you start a service after Netdata, the auto-detected chart may not appear until Netdata restarts. Force detection without restart by running sudo netdatacli reload-health or restarting the specific plugin module.
Health check thresholds may need tuning for your workload: Default alarms (CPU >75%, RAM >80%) will fire on workloads that are perfectly normal for your server. Review /etc/netdata/health.d/ after install and adjust expressions before relying on alerting.

See references/ for: