Query storage status on an RDS DB using AWS CLI

问题

I have a few RDS servers I'd like to monitor for insufficient disk space. For simplicity sake, I prefer using my current monitoring system rather than an AWS solution like cloudwatch.

I've been reading the documentation and the nearest solution was describe-db-instances, which gives the allocated storage, but not the space left / amount of storage used:

"SecondaryAvailabilityZone": "us-east-1a",
"ReadReplicaDBInstanceIdentifiers": [],
"AllocatedStorage": 100,
...

How do I query a specific RDS DB instance for the amount of free space left or used?

回答1:

The right tool is the cloudwatch CLI:

aws cloudwatch get-metric-statistics             \
               --metric-name FreeStorageSpace    \
               --start-time 2017-02-27T23:00:00Z \ 
               --end-time 2017-02-28T23:00:00Z   \
               --period 3600                     \
               --namespace AWS/RDS               \
               --statistics Average              \  
               --dimensions Name=DBInstanceIdentifier,Value=<DB-NAME>

<DB-NAME> and the metric name FreeStorageSpace can be found using:

aws cloudwatch list-metrics

来源：https://stackoverflow.com/questions/42483766/query-storage-status-on-an-rds-db-using-aws-cli