Per-minion schemas cause table count to explode (N minions * M metrics)
and the per-minion revocation story isn't worth it when retention is
short. Move all minions to a shared 'telegraf' schema while keeping
per-minion login credentials for audit.
- New so_telegraf NOLOGIN group role owns the telegraf schema; each
per-minion role is a member and inherits insert/select via role
inheritance
- Telegraf connection string uses options='-c role=so_telegraf' so
tables auto-created on first write belong to the group role
- so-telegraf-trim walks the flat telegraf.* table set instead of
per-minion schemas
- so-stats-show filters by host tag; CLI arg is now the hostname as
tagged by Telegraf rather than a sanitized schema suffix
- Also renames so-show-stats -> so-stats-show
Telegraf's postgresql output stores tag values either as individual
columns on <metric>_tag or as a single JSONB 'tags' column, depending
on plugin version. Introspect information_schema.columns and build the
right accessor per tag instead of assuming one layout.
Introduces global.telegraf_output (INFLUXDB|POSTGRES|BOTH, default BOTH)
so Telegraf can write metrics to Postgres alongside or instead of
InfluxDB. Each minion authenticates with its own so_telegraf_<minion>
role and writes to a matching schema inside a shared so_telegraf
database, keeping blast radius per-credential to that minion's data.
- Per-minion credentials auto-generated and persisted in postgres/auth.sls
- postgres/telegraf_users.sls reconciles roles/schemas on every apply
- Firewall opens 5432 only to minion hostgroups when Postgres output is active
- Reactor on salt/auth + orch/telegraf_postgres_sync.sls provision new
minions automatically on key accept
- soup post_to_3.1.0 backfills users for existing minions on upgrade
- so-show-stats prints latest CPU/mem/disk/load per minion for sanity checks
- so-telegraf-trim + nightly cron prune rows older than
postgres.telegraf.retention_days (default 14)
Mike Reeves