Configure TCP and HTTP health checks on Fly Machines with startup grace period and check intervals.

Documented steps

1. In fly.toml, add a [services] section or [http_service] section for your service
2. For HTTP checks add [[services.http_checks]] (double-bracket TOML array of tables; or [[http_service.checks]] when using http_service) with fields: method (get/post...), path (/health), protocol (http/https), timeout, grace_period (wait after boot before first check), interval
3. For TCP checks, add [[services.tcp_checks]] with fields: grace_period, interval, timeout
4. For Machine checks during deployment, add [services.machine_checks] with fields: image (Docker image), command (test command), kill_signal (timeout signal), kill_timeout (termination duration)
5. Use fly deploy to apply the machine check configuration
6. View health check status with: fly checks list --app <app-name>
7. Note: health checks will fail on non-2xx responses (no automatic redirect following on HTTP 301/302); specify times in milliseconds by default or use units like 5s
8. Docs: https://fly.io/docs/reference/health-checks/