Synth Manage Checks

Synthetic Monitoring Check Manager

Manage Synthetic Monitoring checks using gcx.

Core Principles

1. Use gcx commands; never call Grafana APIs directly (no curl, no HTTP calls)
2. Trust the user's expertise — no explanations of what SM or gcx is
3. Use -o json for agent processing; default table format for user display
4. gcx validates specs client-side before calling the API (probe names, check type, target format) — no separate dry-run step is needed
5. Probe names are case-sensitive — always copy-paste from gcx synthetic-monitoring probes list

Workflow 1: Create New Check

Step 1: Determine Check Type

Pick the type from the target format (full decision tree and per-type templates: check-types.md):

If unsure, ask the user what they want to test (availability, DNS, port connectivity, routing).

Step 2: List and Select Probes

gcx synthetic-monitoring probes list

Recommend at least 3 geographically distributed probes. Copy names exactly as shown — case-sensitive. Suggest probes across different continents or regions to provide meaningful coverage (e.g., one each from North America, Europe, Asia-Pacific).

Step 3: Build YAML Definition

Use the template from check-types.md for the chosen type, filling the type-specific settings block. Common fields:

apiVersion: syntheticmonitoring.ext.grafana.app/v1alpha1
kind: Check
metadata:
  name: <job-name>   # gcx rewrites this to <job>-<id> after create
spec:
  job: <job-name>
  target: <target>
  frequency: 60000    # milliseconds; 10000-120000 typical
  timeout: 10000      # milliseconds; must be < frequency
  enabled: true
  labels:
    - name: environment
      value: production
    - name: team
      value: platform
  probes:
    - Atlanta
    - Frankfurt
    - Singapore
  alertSensitivity: none    # none unless the stack uses legacy sensitivity alerts
  basicMetricsOnly: false   # true = fewer metrics, lower cardinality
  settings:
    http: {}   # Replace with type-specific settings

Configuration guidance:

• frequency: critical checks 10,000–60,000ms; standard checks 60,000–300,000ms
• timeout: must be strictly less than frequency; typically 5,000–30,000ms
• alertSensitivity: default to none — see "Alert Sensitivity" in references/check-types.md for why non-none values can 403 on some stacks.
• basicMetricsOnly: true reduces metric cardinality (fewer label dimensions); false emits full metrics

Step 4: Create the Check

# Create from file
gcx synthetic-monitoring checks create -f <file.yaml>

For HTTP checks, --validate-targets pre-flights the target with a HEAD request (warning only). If client-side validation fails, fix the field named in the error and re-run.

After creation, verify with:

gcx synthetic-monitoring checks list
gcx synthetic-monitoring checks status <ID>

Workflow 2: Update Existing Check

Step 1: Pull Current Definition

Fetch the specific check:

# Get single check as YAML (use ID from list output)
gcx synthetic-monitoring checks get <ID> -o yaml > check-<ID>.yaml

Step 2: Edit and Update

Edit the YAML file, keeping metadata.name unchanged (it is the <job>-<id> composite that targets the right check). Modify only the fields that need changing.

# Update the check from file
gcx synthetic-monitoring checks update <ID> -f check-<ID>.yaml

Workflow 3: GitOps Sync (Pull/Push)

When users say "pull" they mean export with checks get -o yaml; "push" means apply with checks create/checks update -f. Export to files, edit in source control, then update to apply:

# List all checks and export each to YAML
gcx synthetic-monitoring checks list -o yaml

# Get a specific check as YAML
gcx synthetic-monitoring checks get <ID> -o yaml > ./sm-checks/check-<ID>.yaml

# Edit files as needed, then update each changed file
gcx synthetic-monitoring checks update <ID> -f ./sm-checks/check-<ID>.yaml

For bulk updates, update files individually to control which checks are changed.

Workflow 4: Delete Checks

# List checks to confirm IDs
gcx synthetic-monitoring checks list

# Delete one or more checks (by numeric ID)
gcx synthetic-monitoring checks delete <ID>

# Skip confirmation prompt
gcx synthetic-monitoring checks delete <ID> --force

# Delete multiple checks
gcx synthetic-monitoring checks delete <ID1> <ID2> <ID3>

Confirm the check identity (job name and target) before deleting — use gcx synthetic-monitoring checks get <ID> to review.

Output Format

After creating or updating:

Check: <job-name>
Target: <target>
Type: <HTTP|Ping|DNS|TCP|Traceroute>
Probes: <count> selected (<list>)
Result: <created (id=<ID>) | updated>

Verify status:
  gcx synthetic-monitoring checks status <ID>

After export:

Exported <N> checks to <dir>/
Files: <list of filenames>

After delete:

Deleted check <ID> (<job-name> -> <target>)

Error Handling

• "probe not found": Probe names are case-sensitive. Run gcx synthetic-monitoring probes list and copy names exactly.
• "timeout must be less than frequency": Reduce timeout value or increase frequency.
• "invalid frequency": The allowed frequency range depends on check type (e.g. traceroute allows longer intervals); the API error states the valid range.
• "check validation failed": gcx validates the spec client-side before calling the API. Fix the YAML field indicated in the error and re-run.
• Create fails with "check already exists": The check job+target combination may already exist. Use gcx synthetic-monitoring checks list to find it and update instead of create.
• No probes available: Run gcx synthetic-monitoring probes list; if empty, verify gcx context and SM API access.
• Complex check types (MultiHTTP, Browser, Scripted): Settings map is not fully documented. Pull an existing check of that type as a template: gcx synthetic-monitoring checks get <ID> -o yaml.