Grafana

Date: 2026-02-11
Host: FreeBSD jail host
Component: RACCT/RCTL + node_exporter textfile collector
Outcome: Per-jail RAM/VMEM/SWAP metrics in Prometheus/Grafana

Making ZFS ARC Grafana Panels FreeBSD-Compatible

Steps taken to make an imported ZFS/Grafana dashboard work correctly on FreeBSD. Panels assumed Linux exporters and referenced metrics that do not exist on FreeBSD. The result was a dashboard full of empty panels. This walkthrough shows how the missing ARC kstats where identified, cleanly exported and refactored so that the panels reflect the real FreeBSD kernel state.

Host: clemente (10.10.0.1)
Stack: FreeBSD + node_exporter (textfile collector) + Prometheus + Grafana
Date: 2026-02-10

Overview (Context & Goal)

Date: 2026-02-08
Host: grafana
Component: Prometheus + Grafana + exporters +zfs
Scope: ZFS monitoring

ZFS / Zpool Metrics for Prometheus (node-exporter + textfile collector on FreeBSD)

This guide sets up zpool capacity metrics (zpool list) for Prometheus/Grafana using node-exporter’s textfile collector on FreeBSD.

This complements (not replaces) zfs_exporter, which provides ARC/internal ZFS metrics but not pool capacity.

What I Got Working

Metrics exposed to Prometheus:

• zpool_size_bytes{pool="zroot"}
• zpool_alloc_bytes{pool="zroot"}
• zpool_free_bytes{pool="zroot"}
• zpool_capacity_ratio{pool="zroot"}

These map directly to:

Date: 2026-02-08
Host: grafana
Component: Prometheus + Grafana + exporters
Scope: DNS monitoring

Date: 2026-02-08
Host: macOS (MacPorts prefix: /opt/local)
Component: doas (MacPorts)

My WireGuard client app failed to load profiles because the code path relies on doas for privilege escalation. This fix corrects the macOS (MacPorts) doas installation so the client can elevate properly.

doas: not installed setuid

…and exiting with status 1.

Root Cause

On macOS, MacPorts installs doas without the setuid bit by default.

Because doas is not setuid-root, it cannot elevate privileges. Any command relying on it will immediately fail, including:

Date: 2026-02-08
Host: server (macOS Monterey; Homebrew prefix: /usr/local)
Grafana install: Homebrew (/usr/local/opt/grafana)
Grafana data: /usr/local/var/lib/grafana

Grafana (Homebrew on macOS Monterey) & Password Reset + Boot-Time Startup (No GUI Login)

Summary (what was fixed)

1. Admin login/password wouldn’t work even after “reset” attempts.
2. Grafana would run manually, but would not reliably run as a user service via brew services and you needed it to start at boot without any desktop login.
3. fixed both by:

• Resetting the password against the actual Brew paths + DB that the running server uses.
• Replacing the GUI-bound LaunchAgent approach with a system LaunchDaemon at /Library/LaunchDaemons/... that runs at boot as your user.

Caveats

“Password reset succeeded” was misleading because I was hitting the wrong DB

Grafana can be pointed at different data directories. In this setup, the running Brew Grafana server uses: