Monitoring and Alerts

BackupX exposes low-cost health endpoints and a dedicated Prometheus registry. Monitor both the control plane and the outcome of backup, restore, verification, and replication work.

Probes

Endpoint	Meaning	Expected response
/health	Liveness: the HTTP process can respond	HTTP 200 with status: live
/ready	Readiness: the process can reach SQLite	HTTP 200 with status: ready; HTTP 503 on database failure
/api/health	API-prefixed alias for liveness	Same as /health
/api/ready	API-prefixed alias for readiness	Same as /ready
/metrics	Prometheus exposition	HTTP 200 when metrics are enabled

Use /health for a liveness probe and /ready for readiness or load-balancer traffic decisions. Do not restart a process only because an external storage provider is unavailable; storage health belongs in task and target alerts.

curl -fsS http://127.0.0.1:8340/health
curl -fsS http://127.0.0.1:8340/ready
curl -fsS http://127.0.0.1:8340/metrics | head

These endpoints are unauthenticated. Restrict them to orchestrator and monitoring networks.

Prometheus scrape

scrape_configs:
  - job_name: backupx
    scheme: https
    metrics_path: /metrics
    static_configs:
      - targets: [backup.example.com]

When Nginx terminates TLS, allow the Prometheus source address to reach /metrics and deny other public clients. The internal collector refreshes storage, node, command-queue, and SLA gauges every 30 seconds.

BackupX metrics

Metric	Type	Labels	Purpose
backupx_app_info	gauge	version	Running release metadata
backupx_task_run_total	counter	status, task_type	Backup outcomes
backupx_task_run_duration_seconds	histogram	task_type	Backup duration distribution
backupx_task_bytes_total	counter	task_type	Produced backup bytes
backupx_task_running	gauge	none	Current backup concurrency
backupx_storage_used_bytes	gauge	target_name, target_type	Recorded usage per target
backupx_node_online	gauge	node_name, role	Node online state, 1 or 0
backupx_agent_command_queue_depth	gauge	node_name, role	Pending and dispatched commands
backupx_agent_command_running	gauge	node_name, role	Long-running Agent commands
backupx_agent_command_timeout_total	gauge	node_name, role	Snapshot of timed-out commands
backupx_verify_run_total	counter	status	Verification outcomes
backupx_restore_run_total	counter	status	Restore outcomes
backupx_replication_run_total	counter	status	Replication outcomes
backupx_sla_breach_tasks	gauge	none	Enabled tasks outside their configured RPO

Standard Go runtime and process collectors are registered in the same endpoint.

Initial alert rules

Tune windows and thresholds to the schedules and RPOs of each environment:

groups:
  - name: backupx
    rules:
      - alert: BackupXTargetDown
        expr: up{job="backupx"} == 0
        for: 2m
        labels:
          severity: critical
        annotations:
          summary: BackupX metrics endpoint is unreachable

      - alert: BackupXNotReady
        expr: probe_success{job="backupx-ready"} == 0
        for: 2m
        labels:
          severity: critical
        annotations:
          summary: BackupX readiness check is failing

      - alert: BackupXBackupFailure
        expr: sum(increase(backupx_task_run_total{status="failed"}[15m])) > 0
        labels:
          severity: warning
        annotations:
          summary: A BackupX backup failed

      - alert: BackupXSLABreach
        expr: backupx_sla_breach_tasks > 0
        for: 5m
        labels:
          severity: critical
        annotations:
          summary: One or more backup tasks are outside RPO

      - alert: BackupXAgentOffline
        expr: backupx_node_online{role="agent"} == 0
        for: 2m
        labels:
          severity: warning
        annotations:
          summary: BackupX Agent is offline

      - alert: BackupXAgentQueueBacklog
        expr: backupx_agent_command_queue_depth > 20
        for: 10m
        labels:
          severity: warning
        annotations:
          summary: BackupX Agent command queue is growing

The BackupXNotReady example assumes a blackbox probe job named backupx-ready. If no blackbox exporter is used, alert from the load balancer or orchestrator readiness signal instead.

Operational dashboard

Track these views together:

• Success and failure rate by task type.
• P50, P95, and maximum run duration relative to the backup window.
• Bytes produced compared with the expected data-change rate.
• Current running tasks versus backup.max_concurrent.
• Offline Agents, queue depth, running commands, and timeout-count changes.
• Storage growth, free capacity from the storage provider, and retention cleanup.
• SLA breach count and age of the most recent successful backup for critical tasks.
• Verification, restore, and replication success rates.

Prometheus storage usage is based on BackupX record metadata, not necessarily the provider's billable capacity. Monitor provider quota and filesystem free space separately.

Post-deployment validation

After installation, upgrade, proxy changes, or recovery:

1. Check liveness and readiness locally and through the public proxy.
2. Confirm Prometheus sees one active Master and the expected version label.
3. Verify every expected Agent reports backupx_node_online == 1.
4. Run a small backup and confirm the success counter increases.
5. Run a verification or isolated restore and confirm its counter increases.
6. Trigger a test notification and verify the alert delivery path.

Continue with Troubleshooting when a probe or metric is abnormal.