You have an Azure subscription named Sub1 that contains the resources shown in the following...

https://learn.microsoft.com/en-us/azure/azure-monitor/alerts/alerts-processing-rules?tabs=portal#what-should-this-rule-do Suppression: This action removes all the action groups from the affected fired alerts. So, the fired alerts won 't invoke any of their action groups, not even at the end of the maintenance window. Those fired alerts will still be visible when you list your alerts in the portal, Azure Resource Graph, API, or PowerShell.

The alert rule named Alert1 has a scope of all resource groups in Sub1 and includes all future resources. This means that any administrative operation performed on any resource group in Sub1 will trigger the alert rule. The condition of the alert rule is all administrative operations, which includes creating a resource group1. Therefore, if you create a resource group in Sub1 on August 11, 2022, Alert1 will be fired and listed in the Azure portal.

The alert processing rule named Rule1 has a scope of Sub1 and a rule type of suppress notifications. This means that any alert fired in Sub1 will have its notifications suppressed by the rule. The rule applies on a specific time range from August 10, 2022 to August 13, 2022. Therefore, if you create a resource group in Sub1 on August 12, 2022, Alert1 will be fired but no email message will be sent to admin1@contoso.com because of Rule1.

The alert processing rule named Rule1 does not apply after August 13, 2022. Therefore, if you add a tag to RG1 on August 15, 2022, Alert1 will be fired and an email message will be sent to admin1@contoso.com as specified by the action group Action1.