Configure Alerts

  • 6 minutes

Azure Cosmos DB uses the Azure Monitor Service to set up and send alerts. Alerts monitor the availability and responsiveness of Azure Cosmos DB resources and send notifications when monitored metrics hit specified thresholds. Alerts can take the form of emails or even execute Azure Functions when they're triggered. Alerts also monitor the activity log events of your Azure Cosmos DB account.

Alerts can be set up from either your Azure Cosmos DB account page or from Azure Monitor. From both places, you'll set up the alerts in similar fashions.

Setting up an alert

Let's take a look at an example of setting alerts when over one thousand 429 exceptions are triggered within 15 minutes. The alert should check every 5 minutes for the condition. Finally it should send an email to admins@contoso.com when the condition is met.

  1. In your Azure Cosmos DB account page, under the Monitoring section choose Alerts.

  2. Select + Create and select Alert rule to create a new alert. You should see your current Azure Cosmos DB account, subscription, and Resource Group already selected.

  3. Select Add condition. This condition will define the trigger for this alert.

    1. Time to pick the Signal type. Signals are either Metrics or Activity Logs. Since 429 exceptions can occur when requests are made, search for the signal name Total Request Units. We should see a graph that shows us the total request units in the last 6 hours.

    2. Currently if you add an Alert Logic, it will be measured against all the request units for this account. What you need is only to create a condition against the Requests that returned a status code of 429. To create that filter, under Split by dimension choose:

      1. Select StatusCode under the Dimension name pulldown.

      2. Select = under Operator.

      3. If a 429 exception has occurred within the last 6 hours, you could see it under the Dimension values options. If 429 isn't an option under Dimension values, Select Add custom value and add the value 429. You could add extra filters like database, collection, region, or operation type if you needed an even more precise filter.

    3. Set the Alert Logic Threshold value to 1000.

    4. Under Evaluated based on, set the Aggregation granularity (Period) to 15 minutes and the Frequency of Evaluation to 5 minutes.

    5. Select Done to complete the Condition setup.

  4. The alert needs to know what to do when the condition is met. Let's send out the email. Under Actions, select Add action group.

    1. If you already had some actions created, you could reuse them. We'll create a new Action, select + Create action group.

    2. Under the Basic tab:

      1. Give the Action group a name.

      2. If needed, change the Display name.

    3. Under the Notification Tab:

      1. Choose Email/SMS message/Push/Voice under Notification type.

      2. Give the Notification a Name.

      3. Select the pencil icon to add the notification recipient.

        1. Select the Email checkbox.

        2. Set the Email to admins@contoso.com and select OK.

    4. Select the Review + create button and then the Create button

  5. Finally we need to fill out the alert's general information in the Alert Rule details. You can change any of the preselected options as needed, but you need to at least set the Alert rule name, so give the alert a name.

  6. Select the Create alert rule button to create the alert.

Once the alert is created, it can take up to 10 minutes to activate.

Common alerting scenarios

The following are some scenarios where you can use alerts:

  • When the keys of an Azure Cosmos account are updated.
  • When the data or index usage of a container, database, or region exceeds a certain number of bytes.
  • When the normalized RU/s consumption is greater than a certain percentage.
  • When a region is added, removed, or goes offline.
  • When a database or a container is created, deleted, or updated.
  • When the throughput of your database or container is changed.