Monitoring ACK/NAK Non-Events

Proactively monitor and manage ACK/NAK Non-Events with Nodinite to ensure your business never misses a critical response. This guide shows you how to configure, monitor, and act on ACK/NAK Non-Events, so you resolve issues before they impact your operations.

• ✅ Instantly receive alerts for delayed or missing ACK/NAK responses
• ✅ Monitor every ACK/NAK configuration as a unique resource
• ✅ Detect duplicate responses and correlation issues automatically
• ✅ Take immediate action with remote actions and clear state evaluation
• ✅ Analyze alert history for rapid troubleshooting and continuous improvement

Nodinite gives you the power to monitor, alert, and act on ACK/NAK Non-Events with unmatched precision. This guide explains what you monitor, how Nodinite translates technical events into actionable monitoring states, and how you use remote actions to resolve issues instantly. For a deeper dive into available Remote Actions, see the Managing ACK/NAK Non-Events user guide.

You can easily view and manage all monitored ACK/NAK Non-Event configurations in a Nodinite Monitor View.

Monitoring Features

• State Evaluation – Instantly receive alerts when thresholds are breached, so you never miss a critical event!
  • Duration Check – Get alerts when responses are late or missing, so you stay ahead of potential issues.
  • Correlation Count – Receive notifications if you detect too many responses, helping you quickly spot duplicates or anomalies.

Understanding ACK/NAK Monitoring

ACK/NAK (Acknowledgment/Negative Acknowledgment) monitoring tracks request-response patterns in your integration flows. This powerful feature ensures that every request receives the expected response within the defined time window.

What is ACK/NAK monitoring?

ACK/NAK monitoring correlates outgoing requests with incoming responses. You configure Nodinite to expect a specific number of responses (typically 1) for each request within a maximum duration. The system alerts you when:

• Missing responses – A request has no corresponding ACK/NAK within the timeout period
• Delayed responses – A response arrives after the warning threshold but before the error threshold
• Duplicate responses – More responses than expected arrive for a single request

Real-world example:

Diagram: Successful ACK/NAK correlation with response within acceptable timeframe.

How correlation works:

Nodinite ACK/NAK monitoring uses one grouped Log Views result. The monitor evaluates events inside each group (business transaction/interchange) and checks that the next expected event arrives within configured time limits.

Correlation in this mode comes from the grouped Log View design and the searchable values extracted from Log Events (payload/context). In practice, many solutions use an Application Interchange Id or similar business key, but it is not limited to one specific built-in field.

At runtime, the agent:

• Queries the grouped Log View using the configured Log View API URI
• Evaluates timing between related events in the same group
• Applies Warning/Error time spans for delayed or missing expected events
• Optionally evaluates the number of events in each group to detect anomalies and duplicates

Example scenario:

Your e-commerce platform sends order confirmations to a fulfillment system. Each order must receive an acknowledgment within 30 seconds:

• Warning threshold: 20 seconds – Response is slower than expected but acceptable
• Error threshold: 30 seconds – Response is missing or critically delayed
• Grouped correlation key: OrderId – Request and response stay in the same grouped transaction
• Group count evaluation: Enable event-count checks when you also want duplicate/anomaly detection

Monitoring outcomes:

Diagram: Three ACK/NAK monitoring scenarios showing OK (green), Warning (yellow), and Error (red) states based on response timing.

State Evaluation for ACK/NAK Non-Events

Nodinite displays each ACK/NAK configuration as a unique Resource. For example, if you create 42 configurations, you monitor 42 distinct resources, each independently.

• The Resource name matches the ACK/NAK configuration name.
• All configurations appear under the 'ACK/NAK' Category.
• The Application name mirrors the Resource name.

Nodinite continuously evaluates every ACK/NAK configuration (as a Resource) and assigns one of the following states:

With Nodinite, you can easily reconfigure state evaluation at the Resource level using the Expected State feature, so you tailor monitoring to your business needs.

How ACK/NAK Duration Monitoring Works

Understanding how Nodinite evaluates ACK/NAK timing is essential for configuring accurate alerts.

Duration Calculation

Nodinite measures duration using timestamps from Log Events returned by the grouped Log Views. For request-response scenarios, this is typically the elapsed time from the request event to the corresponding response event within the same group.

Formula:

Duration = ExpectedNextEvent.LogDateTime - CurrentEvent.LogDateTime

Threshold Evaluation

You configure two duration thresholds:

Evaluation logic:

Diagram: ACK/NAK duration evaluation flow showing how Nodinite determines resource state based on response timing.

Example Timeline

Configuration:

• Warning Duration: 00:00:20 (20 seconds)
• Error Duration: 00:00:30 (30 seconds)

Scenario 1: Successful Response

10:00:00 - Request sent (LogDateTime)
10:00:12 - ACK received (LogDateTime)
Duration: 12 seconds
Result: OK ✓

Scenario 2: Delayed Response

10:05:00 - Request sent
10:05:25 - ACK received (after warning, before error)
Duration: 25 seconds
Result: Warning ⚠ (Response delayed but received)

Scenario 3: Missing Response

10:10:00 - Request sent
10:10:31 - Still no response (exceeded error duration)
Duration: >30 seconds
Result: Error ✗ (Missing response)

Scenario 4: Very Late Response

10:15:00 - Request sent
10:15:45 - ACK received (after error threshold)
Duration: 45 seconds
Result: Error ✗ (Response too late, treated as failed)

Group Count Evaluation and Duplicate Detection

ACK/NAK monitoring can evaluate event counts per group to identify correlation issues and retry storms.

Evaluate Number of Events in the Group

Enable Evaluate the number of events in the group to apply thresholds on grouped transactions and detect abnormal patterns.

Common outcomes:

• Too few events in a group can indicate missing steps
• Too many events in a group can indicate duplicates, retries, or replay issues
• Combined with duration thresholds, you can detect both late/missing responses and count anomalies

Real-world scenario:

Your payment gateway occasionally retries acknowledgments due to transient network conditions. By combining count evaluation and duration thresholds, you can tolerate expected retry behavior while still alerting on abnormal duplicate patterns.

Visual example of duplicate detection:

Diagram: Grouped event count evaluation showing progression from OK to Warning state as duplicates exceed configured thresholds.

Remote Actions

Take control with powerful remote actions directly from your monitoring dashboard:

• Show missing events – View all requests without corresponding responses
• Show delayed events – Identify responses that arrived late but within error threshold
• Clear previous errors – Acknowledge and clear historical alert states

When to use each action:

Edit Thresholds

Fine-tune your monitoring thresholds for ACK/NAK events in the Configuration user guide. Adjust warning and error durations, and enable group-count evaluation thresholds to match your business SLAs.

Alert History for ACK/NAK Non-Events

You can analyze the frequency and pattern of ACK/NAK Non-Event issues for root cause analysis and continuous improvement. Nodinite lets you search historical state changes for any time span, across all or individual configurations. Learn more in Add or manage Monitor View.

Search	Resource history
Search for alert history for all resources in the Monitor View	Alert history for the selected ACK/NAK configuration

Find answers to common questions and troubleshooting tips in the Troubleshooting guide.

How Do I Enable Monitoring of ACK/NAK Non-Events?

To monitor ACK/NAK Non-Events, select the Enable monitoring checkbox for the Agent (default: checked). See the 'Configuration' user guide for details.

The screenshot below shows the remote configuration form from the Monitoring Agents administration page.

This example shows a disabled ACK/NAK monitoring configuration.

What's the difference between ACK/NAK and Non-Events monitoring?

ACK/NAK Monitoring focuses on request-response correlation:

• Tracks individual request-response pairs
• Monitors response timing (duration)
• Detects missing, delayed, or duplicate responses
• Uses grouped Log View keys to match related events
• Best for: API acknowledgments, message confirmations, two-way integrations

Non-Events Monitoring focuses on volume patterns:

• Tracks total event counts over time periods
• Monitors whether counts fall within expected ranges
• Detects too many or too few events
• Uses time-based intervals (hourly, daily, monthly)
• Best for: Batch processing, scheduled jobs, overall system health

Example comparison:

Why am I getting duplicate warnings when retries are expected?

Tune your group-count evaluation thresholds to accommodate normal retry behavior. For example, if your flow can legitimately emit extra events during retries:

• Keep your Warning and Error time spans unchanged for delay detection
• Adjust count evaluation to tolerate expected extra events in the same group

This setup reduces noise from expected retries while still alerting on abnormal duplicate/replay patterns.

Can I use ACK/NAK monitoring without exact correlation IDs?

Yes, but you still need a stable grouping key in your grouped Log View. ACK/NAK monitoring does not require a field literally named Application Interchange Id; it requires consistent values that keep related events in the same group.

Use this approach:

1. Extract business identifiers with Search Fields for all involved message types
2. Build the grouped Log View so request and response events land in the same group
3. Validate grouping behavior in the Log View before enabling ACK/NAK monitoring

If you cannot establish reliable grouping keys, use Non-Events monitoring for volume-pattern monitoring instead.

How far back does Nodinite look for responses?

Nodinite uses the Search Timespan configured in your ACK/NAK settings. This defines how far back to search for matching requests when evaluating responses.

Example:

• Search Timespan: 7.00:00:00 (7 days)
• During evaluation, Nodinite inspects grouped events within the past 7 days

Best practice: Set the search timespan to at least 2-3 times your error duration to ensure Nodinite can find delayed responses.

Next Step

• Managing ACK/NAK Non-Events

Related Topics

• Prerequisites
• Resources
• Categories
• Applications
• Non-Events Monitoring – For volume-based monitoring
• Search Fields – Configure correlation attributes