Configuring Notifications for MRS Cluster Alarms and Events

MRS uses SMN to offer a publish/subscribe model to achieve one-to-multiple message subscriptions and notifications in a variety of message types (SMSs and emails).

On the MRS management console, you can enable or disable the notification service on the Alarms page. The functions in the following scenarios can be implemented only after the required cluster function is enabled:

After a user subscribes to the notification service, the MRS management plane notifies the user of success or failure of manual cluster scale-out and scale-in, cluster deletion, and auto scaling by emails or SMS messages.
The management plane checks the alarms about the MRS cluster and sends a notification to the tenant if the alarms are critical.
If either of the operations such as deletion, shutdown, specifications modification, restart, and OS update is performed on an ECS in a cluster, the MRS cluster works abnormally. The management plane notifies a user when detecting that the VM of the user is in either of the preceding operations.

Creating a Topic

A topic is a specified event for message publication and notification subscription. It serves as a message sending channel, where publishers and subscribers can interact with each other.

Log in to the management console.
Click Service List. Under Management & Governance, click Simple Message Notification.

The SMN page is displayed.
In the navigation pane, choose Topic Management > Topics.

The Topics page is displayed.
Click Create Topic.

The Create Topic dialog box is displayed.
In Topic Name, enter a topic name. In Display Name, enter a display name.
Select an existing project from the Enterprise Project drop-down list, or click Create Enterprise Project to create an enterprise project on the Enterprise Project Management page and then select it.
Set tag keys and tag values. Tags consist of keys and values. They identify cloud resources so that you can easily categorize and search for your resources.

Adding Subscriptions to a Topic

To deliver messages published to a topic to subscribers, you must add subscription endpoints to the topic. SMN automatically sends a confirmation message to the subscription endpoint. The confirmation message is valid only within 48 hours. The subscribers must confirm the subscription within 48 hours so that they can receive notification messages. Otherwise, the confirmation message becomes invalid, and you need to send it again.

Log in to the management console.
Under Management & Governance, click Simple Message Notification.

The SMN page is displayed.
In the navigation pane, choose Topic Management > Topics.

The Topics page is displayed.
Locate the topic to which you want to add a subscription, click More in the Operation column, and select Add Subscription.

The Add Subscription box is displayed.

Endpoint indicates the address of the subscription endpoint. SMS and email, endpoints can be entered in batches. When adding endpoints in batches, each endpoint address occupies a line. You can enter a maximum of 10 endpoints.
Click OK.

The subscription you added is displayed in the subscription list.

Sending Notifications to Subscribers

Log in to the MRS console.
Choose Active Clusters, select a running cluster, and click its name to go to its details page.
Click Alarms.
Choose Notification Rules > Add Notification Rule.

Figure 1 Creating a message subscription rule

Set the notification rule parameters.

**Table 1** Parameters of a notification rule
Parameter	Description
Rule Name	User-defined notification rule name. Only digits, letters, hyphens (-), and underscores (_) are allowed.
Message Notification	If you enable this function, the system sends notifications to subscribers based on the notification rule. If you disable this function, the rule does not take effect, that is, notifications are not sent to subscribers.
Topic Name	Select an existing topic or click Create Topic to create a topic.
Notification Type	Select the type of the notification to be subscribed to. Alarm Event
Subscription Items	Select the items to be subscribed to. You can select all or some items as required. Subscription rules in MRS 3.x or later: Alarm severity: critical, major, minor, and suggestion Event: major, minor, and warning Subscription rules in versions earlier than MRS 3.x: Alarm: critical, major, and minor Event: major, minor, and warning