To modify an Amazon DocumentDB subnet group

The following modify-db-subnet-group example modifies the subnet group sample-subnet-group by adding the specified subnets and a new description.

aws docdb modify-db-subnet-group \
    --db-subnet-group-name sample-subnet-group \
    --subnet-ids subnet-b3806e8f subnet-53ab3636 subnet-991cb8d0 \
    --db-subnet-group-description "New subnet description"

Output:

{
    "DBSubnetGroup": {
        "DBSubnetGroupName": "sample-subnet-group",
        "SubnetGroupStatus": "Complete",
        "DBSubnetGroupArn": "arn:aws:rds:us-west-2:123456789012:subgrp:sample-subnet-group",
        "VpcId": "vpc-91280df6",
        "DBSubnetGroupDescription": "New subnet description",
        "Subnets": [
            {
                "SubnetIdentifier": "subnet-b3806e8f",
                "SubnetStatus": "Active",
                "SubnetAvailabilityZone": {
                    "Name": "us-west-2a"
                }
            },
            {
                "SubnetIdentifier": "subnet-53ab3636",
                "SubnetStatus": "Active",
                "SubnetAvailabilityZone": {
                    "Name": "us-west-2c"
                }
            },
            {
                "SubnetIdentifier": "subnet-991cb8d0",
                "SubnetStatus": "Active",
                "SubnetAvailabilityZone": {
                    "Name": "us-west-2b"
                }
            }
        ]
    }
}

For more information, see Modifying an Amazon DocumentDB Subnet Group in the Amazon DocumentDB Developer Guide.