Traceroute Monitor Configuration

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Basic Setup

• Hostname or IP address: The host to trace to (e.g. api.example.com or 203.0.113.1). Do not include a scheme or port in this field
• IP family: Choose between IPv4 (default) or IPv6
• Protocol: The probe protocol. TCP (default) is the most firewall-friendly option. See the protocol reference for details on TCP, UDP, ICMP, and SCTP
• Port: Destination port for TCP, UDP, and SCTP probes (1–65535). Defaults to 443 for TCP and 33434 for UDP/SCTP. Not applicable for ICMP — the port field is hidden when ICMP is selected
• Max Hops: Maximum number of hops to probe before stopping (1–64, default: 30)
• Max Unknown Hops: Maximum number of consecutive unresponsive hops to tolerate before cutting the trace short (1–30, default: 15). Many routers silently drop traceroute probes without affecting real traffic, so a reasonable limit prevents traces from halting unnecessarily
• Timeout: Maximum time in seconds to wait for the entire trace to complete (1–30, default: 10)
• Reverse DNS (PTR lookup): When enabled (default: on), Checkly performs a PTR lookup on each hop IP to resolve it to a hostname. Disable to reduce trace time when hostnames are not needed

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Assertions

• Latency: RTT statistics for the final responding hop. Available properties: avg, min, max, stdDev (all in milliseconds). This assertion requires the destination to be reached — if destinationReached is false, finalHopLatency is absent and the assertion fails
• Hop Count: Total number of hops recorded in the trace. Use this to detect routing changes that add or remove hops from the expected path
• Packet Loss: Packet loss percentage at the last recorded hop (0–100). A non-zero value indicates that some probe packets were not returned

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Response Time Limits

• Degraded After: Final-hop avg RTT threshold (in milliseconds) after which the check is marked as degraded but not failed. Default: 3,000 ms. Maximum: 30,000 ms
• Failed After: Final-hop avg RTT threshold after which the check fails completely. Default: 5,000 ms. Maximum: 30,000 ms

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JSON Response Schema

{
  "hostname": "api.example.com",          // Target hostname or IP as configured
  "resolvedIp": "93.184.216.34",          // IP address used for the trace
  "port": 443,                             // Destination port; for ICMP probes this reports the unused fallback 443
  "ipFamily": "IPv4",                      // "IPv4" or "IPv6"
  "maxHops": 30,                           // Configured max hops
  "totalHops": 12,                         // Number of hops actually recorded
  "destinationReached": true,              // Whether the destination responded
  "truncationReason": "destinationReached",// Why the trace stopped:
                                           // "destinationReached" | "maxHops" | "maxUnknownHops" | "timeout"
  "probeProtocol": "TCP",                 // Probe protocol: "TCP" | "UDP" | "ICMP" | "SCTP"
  "finalHopLatency": {                     // RTT stats for the last responding hop (the whole object is omitted when the destination is not reached)
    "avg": 12.34,
    "min": 11.80,
    "max": 13.10,
    "stdDev": 0.42
  },
  "hops": [
    {
      "hop_number": 1,
      "main_ip": "10.0.0.1",              // Primary IP observed at this hop
      "main_host": "router.isp.net",      // Reverse-DNS hostname (omitted when PTR lookup is off or the lookup fails)
      "sent": 3,                           // Probe packets sent to this hop
      "received": 3,                       // Replies received from this hop
      "loss_percentage": 0.0,             // Packet loss at this hop
      "rtt": {                             // RTT stats (omitted when the hop never replied)
        "last_ms": 1.23,                 // RTT of the most recent probe
        "avg_ms": 1.10,                  // Average RTT across all probes
        "best_ms": 0.95,                 // Minimum RTT
        "worst_ms": 1.23,               // Maximum RTT
        "stddev_ms": 0.12               // Standard deviation
      },
      "asn": 15169,                        // Autonomous System Number (omitted when unknown)
      "asn_org": "GOOGLE",               // AS organization name (omitted when unknown)
      "country": "US",                   // Two-letter country code (omitted when unknown)
      "aws_region": "us-east-1",         // AWS region — only present when the hop is inside AWS
      "aws_service": "EC2"               // AWS service — only present when the hop is inside AWS
    }
    // ... one entry per recorded hop
  ],
  "timestamp": 1720000000                 // Unix timestamp of the trace run
}

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Frequency

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Scheduling & Locations

• Strategy: Choose between round-robin or parallel execution. Learn more about scheduling strategies
• Locations: Select public or private locations to run the monitor from

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Additional Settings

• Name: Give your monitor a clear name to identify it in dashboards and alerts
• Description: Add context about what this monitor does and why it matters. Supports markdown, max 500 characters. When a failure occurs, Rocky AI uses the description to provide more accurate root cause and user impact analysis
• Tags: Use tags to organize monitors across dashboards and maintenance windows
• Retries: Define how failed runs should be retried. See retry strategies
• Alerting: Configure your alert settings, alert channels, or set up webhooks for custom integrations