# Monitoring CloudWatch Cluster and Node Metrics
<a name="CloudWatchMetrics"></a>

ElastiCache and CloudWatch are integrated so you can gather a variety of metrics. You can monitor these metrics using CloudWatch. 

**Note**  
The following examples require the CloudWatch command line tools. For more information about CloudWatch and to download the developer tools, see the [ CloudWatch product page](https://aws.amazon.com/cloudwatch). 

The following procedures show you how to use CloudWatch to gather storage space statistics for an cluster for the past hour. 

**Note**  
The `StartTime` and `EndTime` values supplied in the examples below are for illustrative purposes. You must substitute appropriate start and end time values for your cache nodes.

For information on ElastiCache limits, see [AWS Service Limits](https://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html#limits_elasticache) for ElastiCache.

## Monitoring CloudWatch Cluster and Node Metrics (Console)
<a name="CloudWatchMetrics.CON"></a>

 **To gather CPU utilization statistics for a cache cluster** 

1. Sign in to the AWS Management Console and open the ElastiCache console at [ https://console.aws.amazon.com/elasticache/](https://console.aws.amazon.com/elasticache/).

1. Select the cache nodes you want to view metrics for. 
**Note**  
Selecting more than 20 nodes disables viewing metrics on the console.

   1. On the **Cache Clusters** page of the AWS Management Console, click the name of one or more clusters.

      The detail page for the cluster appears. 

   1. Click the **Nodes** tab at the top of the window.

   1. On the **Nodes** tab of the detail window, select the cache nodes that you want to view metrics for.

      A list of available CloudWatch Metrics appears at the bottom of the console window. 

   1. Click on the **CPU Utilization** metric. 

      The CloudWatch console will open, displaying your selected metrics. You can use the **Statistic** and **Period** drop-down list boxes and **Time Range** tab to change the metrics being displayed. 

## Monitoring CloudWatch Cluster and Node Metrics using the CloudWatch CLI
<a name="CloudWatchMetrics.CLI"></a>

 **To gather CPU utilization statistics for a cache cluster** 
+ For Linux, macOS, or Unix:

  ```
  aws cloudwatch get-metric-statistics \
      --namespace AWS/ElastiCache \
      --metric-name CPUUtilization \
      --dimensions='[{"Name":"CacheClusterId","Value":"test"},{"Name":"CacheNodeId","Value":"0001"}]' \					
      --statistics=Average \
      --start-time 2018-07-05T00:00:00 \
      --end-time 2018-07-06T00:00:00 \
      --period=3600
  ```

  For Windows:

  ```
  aws cloudwatch get-metric-statistics ^
      --namespace AWS/ElastiCache ^
      --metric-name CPUUtilization ^
      --dimensions='[{"Name":"CacheClusterId","Value":"test"},{"Name":"CacheNodeId","Value":"0001"}]' ^
      --statistics=Average ^
      --start-time 2018-07-05T00:00:00 ^
      --end-time 2018-07-06T00:00:00 ^
      --period=3600
  ```

## Monitoring CloudWatch Cluster and Node Metrics using the CloudWatch API
<a name="CloudWatchMetrics.API"></a>

 **To gather CPU utilization statistics for a cache cluster** 
+ Call the CloudWatch API `GetMetricStatistics` with the following parameters (note that the start and end times are shown as examples only; you will need to substitute your own appropriate start and end times):
  + `Statistics.member.1``=Average`
  + `Namespace``=AWS/ElastiCache`
  + `StartTime``=2013-07-05T00:00:00`
  + `EndTime``=2013-07-06T00:00:00`
  + `Period``=60`
  + `MeasureName``=CPUUtilization`
  + `Dimensions``=CacheClusterId=mycachecluster,CacheNodeId=0002`  
**Example**  

  ```
   1. http://monitoring.amazonaws.com/
   2.     ?Action=GetMetricStatistics
   3.     &SignatureVersion=4
   4.     &Version=2014-12-01
   5.     &StartTime=2018-07-05T00:00:00
   6.     &EndTime=2018-07-06T23:59:00
   7.     &Period=3600
   8.     &Statistics.member.1=Average
   9.     &Dimensions.member.1="CacheClusterId=mycachecluster"
  10.     &Dimensions.member.2="CacheNodeId=0002"
  11.     &Namespace=&AWS;/ElastiCache
  12.     &MeasureName=CPUUtilization						
  13.     &Timestamp=2018-07-07T17%3A48%3A21.746Z
  14.     &AWS;AccessKeyId=<&AWS; Access Key ID>
  15.     &Signature=<Signature>
  ```