abhi, thank you for the question.
Please find below the answers to your questions:
- There are no pre-requisites to configuration of alerts for any instances. However, depending on the type of alert being configured, specific resources will have to be created. For example, if you want to get an alert based on the available storage space on a VM, the specific alert rule will have to be created. This may be based on Logs or Metrics. Also, depending on how you want to be notified of the alerts (email, sms or some other action), for which again the required resources will have to be configured. Therefore, it will depend on the type of alert you are creating in Azure.
To assist the users, most of the Azure resources already have recommended set of alerts that should be set (they are not set by default, but alert rule needs to be created). For details, see Enable recommended alert rules in the Azure portal. Note that while Azure does recommend a predefined set of alerts that you can configure, they are not enabled by default and should be done using the link shared earlier. - Regarding your other question - There are very basic sets of alert notifications sent out by default - for example subscription management, billing cap reached etc. However, those will be sent to the subscription owners.
I would suggest you review Azure Advisor, which helps you follow best practices to optimize your Azure deployments. It analyzes your resource configuration and usage telemetry and then recommends solutions that can help you improve the cost effectiveness, performance, Reliability (formerly called High availability), and security of your Azure resources. The email notifications to set of users can be configured using Azure Advisor using the link below: Create Azure Advisor alerts on new recommendations using the Azure portal - The Azure Active Directory Identity Protection notifications are also something that are sent by default. For details of recipients of this alert, see this link.
Hope this helps.
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