# Hecate

Hecate is the host-level bootstrap and power-protection service for Titan.

It runs on `titan-db` and handles:
- Staged **startup** (including Flux/Gitea bootstrap deadlock fallback)
- Graceful **shutdown**
- UPS-driven automatic shutdown decisions based on discharge/runtime
- Multi-UPS operation via multiple Hecate instances (for example `titan-db` + `tethys`)
- Full hardware poweroff sequencing after graceful Kubernetes shutdown

## Why host-level

A service inside Kubernetes cannot start a cluster that is fully down.
Hecate runs outside the cluster under systemd, so it can always orchestrate bring-up.

## Commands

- `hecate startup --config /etc/hecate/hecate.yaml --execute --force-flux-branch main`
- `hecate shutdown --config /etc/hecate/hecate.yaml --execute`
- `hecate daemon --config /etc/hecate/hecate.yaml`
- `hecate status --config /etc/hecate/hecate.yaml`

Key startup guards:
- Startup is blocked on hosts configured as `coordination.role: peer` (unless `--allow-peer-startup` is used intentionally).
- `--auto-peer-failover` makes peer hosts hand off startup to the coordinator first, then run local startup only if the coordinator is unreachable.
- Startup is blocked while UPS is on battery by default (unless `--allow-on-battery` or `coordination.allow_startup_on_battery: true` is set).
- Startup is blocked when a shutdown intent is active (`/var/lib/hecate/intent.json`).

## Manual install on titan-db

```bash
git clone git@gitea-admin:bstein/hecate.git
cd hecate
sudo HECATE_ENABLE_BOOTSTRAP=1 ./scripts/install.sh
sudoedit /etc/hecate/hecate.yaml
sudo systemctl restart hecate.service
```

The installer is idempotent:
- Re-runs safely on every update
- Preserves existing `/etc/hecate/hecate.yaml`
- Automatically migrates legacy defaults (for example `default_budget_seconds: 300` and `runtime_safety_factor: 1.10`)
- Ensures required dependencies are installed (`kubectl`, `nut-*`, `ssh`, `go`, etc.)
- Installs/refreshes systemd units and enables boot-time self-update
- Applies declarative NUT + udev UPS configuration by default (can be tuned via env vars)

Installer knobs (optional):
- `HECATE_ENABLE_BOOTSTRAP=1` enables `hecate-bootstrap.service` on this host.
- `HECATE_ENABLE_BOOTSTRAP=0` disables it; default `auto` enables bootstrap by default.
- `HECATE_MANAGE_NUT=0` skips writing NUT/udev files.
- `HECATE_FORCE_CONFIG_TEMPLATE=coordinator|peer|example` overwrites `/etc/hecate/hecate.yaml` from a known template during install.
- `HECATE_NUT_UPS_NAME` (default inferred from `/etc/hecate/hecate.yaml` target, fallback `pyrphoros`)
- `HECATE_NUT_VENDOR_ID` / `HECATE_NUT_PRODUCT_ID` (defaults `0764` / `0601`)
- `HECATE_NUT_MONITOR_USER` / `HECATE_NUT_MONITOR_PASSWORD` (defaults `monuser` / `hecateupsmon`)

Bootstrap now (without reboot):

```bash
sudo systemctl start hecate-bootstrap.service
```

## Preconditions on titan-db

- `kubectl` installed and configured (`kubeconfig` path in config)
- SSH reachability to all cluster nodes
- Remote sudo rights to run:
  - `systemctl start/stop k3s`
  - `systemctl start/stop k3s-agent`
- UPS telemetry available via NUT (`upsc`)

Optional SSH jump/bastion:
- Set `ssh_jump_host` (and optional `ssh_jump_user`) to route node SSH through a jump host like `titan-jh`; Hecate now falls back to direct SSH automatically if jump routing is unavailable.
- Set `ssh_port`, `ssh_config_file`, `ssh_identity_file`, and `ssh_node_hosts` so root-run systemd actions can actually reach node SSH daemons during cold-start recovery.
- Use `ssh_node_users` for per-node username overrides (for example `titan-24: tethys`).
- Use `ssh_managed_nodes` to limit host-level SSH start/stop actions to nodes Hecate can actually authenticate to.

## Multi-UPS topology

Recommended:
- `titan-db` runs Hecate as the shutdown coordinator with UPS `Pyrphoros` (`pyrphoros@localhost`).
- `tethys` runs Hecate as a peer with UPS `Statera` (`statera@localhost`) and forwards shutdown triggers to `titan-db`.
- The bootstrap unit now runs on both roles; peer role uses auto-failover handoff to coordinator before local fallback startup.
- If forwarding fails, fallback local shutdown can remain enabled.
- Use `coordination.role: coordinator` on `titan-db` and `coordination.role: peer` on `tethys`.

## Config

See `configs/hecate.example.yaml`.

UPS auto-shutdown trigger uses:
- runtime threshold = `runtime_safety_factor * estimated_shutdown_budget`
- default safety factor `1.25`
- debounce across multiple polls to avoid noise

Estimated shutdown budget is derived from historical successful shutdown runs (`/var/lib/hecate/runs.json`) with default fallback from config.

Power metrics:
- Hecate exposes Prometheus metrics on `:9560/metrics` by default.
- This is intended for a dedicated Grafana power dashboard and a high-level overview row.

## Notes

- Default behavior for `startup` and `shutdown` is dry-run unless `--execute` is set.
- Hecate tracks intent in `/var/lib/hecate/intent.json` (`normal`, `startup_in_progress`, `shutting_down`, `shutdown_complete`) to avoid startup/shutdown fighting each other.
- `hecate-bootstrap.service` is enabled to run at host boot and perform staged startup automatically.
- `HECATE_ENABLE_BOOTSTRAP=1` forces bootstrap on, `HECATE_ENABLE_BOOTSTRAP=0` forces it off, and `auto` enables by default.
- `hecate-update.timer` runs on boot and periodically to pull latest `main` and reinstall Hecate declaratively.
- Peer startup fallback now checks coordinator intent/bootstrap activity before allowing local startup.
- Automatic etcd recovery can run during startup if API never becomes reachable (`startup.auto_etcd_restore_on_api_failure`).

## Etcd Recovery

- Manual: `hecate etcd-restore --config /etc/hecate/hecate.yaml --execute`
- Optional snapshot override: `--snapshot /var/lib/rancher/k3s/server/db/snapshots/<name>`
- Startup can automatically invoke the same restore path after API timeout using:
  - `startup.auto_etcd_restore_on_api_failure: true`
  - `startup.etcd_restore_control_plane: <control-plane-node>`

## Disruptive startup drills

Hecate includes scripted disruptive drills that intentionally break critical services and verify startup recovery paths:

- `scripts/hecate-drills.sh list`
- `scripts/hecate-drills.sh run flux-gitea-deadlock --execute`
- `scripts/hecate-drills.sh run foundation-recovery --execute`
- `scripts/hecate-drills.sh run reconciliation-resume --execute`

These drills are intentionally **not** part of regular `go test ./...`.