Although the metrics we covered earlier will give you good insight into how well your cluster is performing, you can also directly query Amazon DocumentDB for the status of a cluster or individual instances.
Cluster or instance status does not tell you how well the database is performing in terms of servicing database clients. However, it does give you visibility into whether the cluster or instance is available, undergoing routine maintenance, upgrading, or experiencing an outage.
You can retrieve cluster or instance status on the console or through the AWS CLI or SDKs. Here is an example of getting cluster status using the AWS CLI:
aws docdb describe-db-clusters --db-cluster-identifier getting-started-with-documentdb --query 'DBClusters[*].[DBClusterIdentifier,Status]'
Here is an example of getting an individual instance status using the AWS CLI:
aws docdb describe-db-instances --db-instance-identifier getting-started-with-documentdb --query 'DBInstances[*].[DBInstanceIdentifier,DBInstanceStatus]'
Besides doing an ad-hoc status check, you can integrate database status into an overall application health dashboard in one of two ways.