You can filter alarm subsets and then group them based on the grouping conditions. Alarms in the same group are aggregated to trigger one notification.

As shown in Figure 1, when Alarm Severity under Grouping Condition is set to Critical, the system filters out the critical alarms, and then combines these alarms based on the specified mode. The combined alarms can then be associated with an action rule for sending notifications.

Figure 1 Grouping process

Creating a Grouping Rule

You can create up to 100 grouping rules.

In the navigation pane, choose Alarm Center > Alarm Noise Reduction.

On the Grouping Rules tab page, click Create and set parameters such as the rule name and grouping condition. For details, see Table 1.

Figure 2 Creating a grouping rule

**Table 1** Setting a grouping rule
Category	Parameter	Description
-	Rule Name	Grouping rule name, which can contain up to 100 characters and cannot start or end with an underscore (_). Only letters, digits, and underscores are allowed.
-	Description	Grouping rule description, which can contain up to 1024 characters.
Grouping rules	Grouping Condition	Conditions set to filter alarms. After alarms are filtered out, you can set alarm action rules for them. You can create a maximum of 10 parallel conditions, each of which can contain up to 10 serial conditions. One or more alarm action rules can be set for each parallel condition. Serial conditions are in the AND relationship whereas parallel conditions are in the OR relationship. An alarm must meet all serial conditions under one of the parallel conditions. For example, if two serial conditions (that is, Alarm Severity = Critical and Provider = AOM) are set under a parallel condition, critical AOM alarms are filtered out, and notification actions are performed based on the alarm action rule you set.
Combination rules	Combine Notifications	Notifications for alarms with certain fields to be the same will be combined. Notifications can be combined: By alarm source By alarm source + severity By alarm source + all tags
	Initial Wait Time	Interval for sending an alarm notification after alarms are combined for the first time. It is recommended that the time be set to seconds to prevent alarm storms. Value range: 0s to 10 minutes. Recommended: 15s.
	Batch Processing Interval	Waiting time for sending an alarm notification after the combined alarm data changes. It is recommended that the time be set to minutes. If you want to receive alarm notifications as soon as possible, set the time to seconds. The change here refers to a new alarm or an alarm status change. Value range: 5s to 30 minutes. Recommended: 60s.
	Repeat Interval	Waiting time for sending an alarm notification after the combined alarm data becomes duplicate. It is recommended that the time be set to hours. Duplication means that no new alarm is generated and no alarm status is changed while other attributes (such as titles and content) are changed. Value range: 0 minutes to 15 days. Recommended: 1 hour.

Click Create Now.

More Operations

After creating a grouping rule, perform the operations listed in Table 2 if needed.

**Table 2** Related operations
Operation	Description
Modifying a grouping rule	Click Modify in the Operation column.
Deleting a grouping rule	To delete a single rule, click Delete in the Operation column in the row that contains the rule. To delete one or more rules, select them and click Delete above the rule list.
Searching for a grouping rule	Enter a rule name in the search box in the upper right corner and click .