Using template variables in CloudWatch queries

Instead of hard-coding server, application, and sensor names in your metric queries, you can use variables. The variables are listed as dropdown select boxes at the top of the dashboard. These dropdowns make it easy to change the display of data in your dashboard.

For an introduction to templating and template variables, refer to the Templating documentation.

Query variable

The CloudWatch data source provides the following queries that you can specify in the Query field in the Variable edit view. They allow you to fill a variable’s options list with things like region, namespaces, metric names and dimension keys/values.

In place of region you can specify default to use the default region configured in the data source for the query, e.g. metrics(AWS/DynamoDB, default) or dimension_values(default, ..., ..., ...).

Read more about the available dimensions in the CloudWatch Metrics and Dimensions Reference.

NameDescription
regions()Returns a list of all AWS regions
namespaces()Returns a list of namespaces CloudWatch support.
metrics(namespace, [region])Returns a list of metrics in the namespace. (specify region or use “default” for custom metrics)
dimension_keys(namespace)Returns a list of dimension keys in the namespace.
dimension_values(region, namespace, metric, dimension_key, [filters])Returns a list of dimension values matching the specified region, namespace, metric, dimension_key or you can use dimension filters to get more specific result as well.
ebs_volume_ids(region, instance_id)Returns a list of volume ids matching the specified region, instance_id.
ec2_instance_attribute(region, attribute_name, filters)Returns a list of attributes matching the specified region, attribute_name, filters.
resource_arns(region, resource_type, tags)Returns a list of ARNs matching the specified region, resource_type and tags.
statistics()Returns a list of all the standard statistics

For details about the metrics CloudWatch provides, please refer to the CloudWatch documentation.

Example of templated queries

Here is an example of the dimension queries which will return list of resources for individual AWS Services:

QueryService
dimension_values(us-east-1,AWS/ELB,RequestCount,LoadBalancerName)ELB
dimension_values(us-east-1,AWS/ElastiCache,CPUUtilization,CacheClusterId)ElastiCache
dimension_values(us-east-1,AWS/Redshift,CPUUtilization,ClusterIdentifier)RedShift
dimension_values(us-east-1,AWS/RDS,CPUUtilization,DBInstanceIdentifier)RDS
dimension_values(us-east-1,AWS/S3,BucketSizeBytes,BucketName)S3
dimension_values(us-east-1,CWAgent,disk_used_percent,device,{“InstanceId”:”$instance_id”})CloudWatch Agent
resource_arns(eu-west-1,elasticloadbalancing:loadbalancer,{“elasticbeanstalk:environment-name”:[“myApp-dev”,”myApp-prod”]})ELB
resource_arns(eu-west-1,elasticloadbalancing:loadbalancer,{“Component”:[“$service”],”Environment”:[“$environment”]})ELB
resource_arns(eu-west-1,ec2:instance,{“elasticbeanstalk:environment-name”:[“myApp-dev”,”myApp-prod”]})EC2

Using JSON format template variables

Some queries accept filters in JSON format and Grafana supports the conversion of template variables to JSON.

If env = 'production', 'staging', following query will return ARNs of EC2 instances which Environment tag is production or staging.

  1. resource_arns(us-east-1, ec2:instance, {"Environment":${env:json}})

ec2_instance_attribute examples

JSON filters

The ec2_instance_attribute query takes filters in JSON format. You can specify pre-defined filters of ec2:DescribeInstances. Note that the actual filtering takes place on Amazon’s servers, not in Grafana.

Filters syntax:

  1. { "filter_name1": [ "filter_value1" ], "filter_name2": [ "filter_value2" ] }

Example ec2_instance_attribute() query

  1. ec2_instance_attribute(us - east - 1, InstanceId, { 'tag:Environment': ['production'] });

Selecting attributes

Only 1 attribute per instance can be returned. Any flat attribute can be selected (i.e. if the attribute has a single value and isn’t an object or array). Below is a list of available flat attributes:

  • AmiLaunchIndex
  • Architecture
  • ClientToken
  • EbsOptimized
  • EnaSupport
  • Hypervisor
  • IamInstanceProfile
  • ImageId
  • InstanceId
  • InstanceLifecycle
  • InstanceType
  • KernelId
  • KeyName
  • LaunchTime
  • Platform
  • PrivateDnsName
  • PrivateIpAddress
  • PublicDnsName
  • PublicIpAddress
  • RamdiskId
  • RootDeviceName
  • RootDeviceType
  • SourceDestCheck
  • SpotInstanceRequestId
  • SriovNetSupport
  • SubnetId
  • VirtualizationType
  • VpcId

Tags can be selected by prepending the tag name with Tags.

Example ec2_instance_attribute() query

  1. ec2_instance_attribute(us - east - 1, Tags.Name, { 'tag:Team': ['sysops'] });