Add a `hostname` label to all Prometheus scrape targets, making it easy
to query all metrics for a host without wildcarding the instance label.
Example queries:
- {hostname="ns1"} - all metrics from ns1
- node_cpu_seconds_total{hostname="monitoring01"} - specific metric
For external targets (like gunter), the hostname is extracted from the
target string.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Extract homelab.host metadata (tier, priority, role, labels) from host
configurations and propagate them to Prometheus scrape targets. This
enables semantic alert filtering using labels instead of hardcoded
instance names.
Changes:
- lib/monitoring.nix: Extract host metadata, group targets by labels
- prometheus.nix: Use structured static_configs with labels
- rules.yml: Replace instance filters with role-based filters
Example labels in Prometheus:
- ns1/ns2: role=dns, dns_role=primary/secondary
- nix-cache01: role=build-host
- testvm*: tier=test
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Add homelab.monitoring NixOS options (enable, scrapeTargets) following
the same pattern as homelab.dns. Prometheus scrape configs are now
auto-generated from flake host configurations and external targets,
replacing hardcoded target lists.
Also cleans up alert rules: snake_case naming, fix zigbee2mqtt typo,
remove duplicate pushgateway alert, add for clauses to monitoring_rules,
remove hardcoded WireGuard public key, and add new alerts for
certificates, proxmox, caddy, smartctl temperature, filesystem
prediction, systemd state, file descriptors, and host reboots.
Fixes grafana scrape target port from 3100 to 3000.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
