OCI Observability and Management (O&M) Platform consists of several cloud services that we can enable to monitor, analyze, and manage applications and infrastructure environments with full-stack visibility, prebuilt analytics, and automation capabilities.
In this blog, I will create an alarm that is triggered when the service metrics reach a designated threshold, and using OCI notification we will get a notification alert.
Steps:
1. Confirm compute instance monitoring Plug-in is Enabled
Navigate to Main Menu -> Compute -> Instances and select your instance
Click on the Oracle Cloud Agent tab.
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The compute instance monitoring plug-in should be running and enabled.
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2. Create a Topic and Subscription Inside a Topic for Notification
To create an alarm, first I need to create a notification so that the alarm has a way to notify the relevant parties.
OCI Notification has two main elements: Topic (a communication channel for sending alarms) and Subscription (endpoints for receiving those messages)
Navigate to Main Menu –> Developer Services –> Application Integration, and select Notifications.
Click Create Topic and give any topic name ( for eg. CPU stress-topic) and description and click create.
After the topic state changes to Active, click the topic Name.
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Now Click Create Subscription, Provide the Protocol name and detail
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Click create and you will see your subscription OCID.
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The subscription details screen will be displayed with the subscription status pending.
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I should receive an email to confirm the subscription with Confirm subscription verification link in it. Like below..
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Verify the subscription by clicking on Confirm subscription and then you will see the subscription status changes to active in the OCI console.
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3. Now the final step is to create an alarm for CPU Utilization
Navigate to Main Menu -> Observability & Management -> Monitoring and click Alarm Definitions.
Click Create Alarm.
a. Define Alarm
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b. Define Metric description like compartment, metric namespace (oci_computeagent), Metric name, interval, and statistics like below.
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I leave the metric dimensions area blank as I have only one compute instance but if you have like 5 or more instances then you can use dimensions to filter based on dimensions.
c. Define trigger rule: you can use any value as per requirement.
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d. Define Alarm Notifications: Here you have to mention the Topic that we created in step 2.
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e. We can also select the message format and repeat notification if an alarm continues. Or you can suppress the notification.
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f. Check Enable this alarm and save it.
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You should now be able to see the alarm’s details when you click on Alarm like below.
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And when the threshold reaches to >=70 as per the alarm setup, we will get an email notification like below.
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Email provides details about Alarm OCID, number of metrics breaching threshold, and dimensions.
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Stay Tuned for my next O&M Blog!