Tutorial for adding a new Prometheus scrape target: Memcached on Amazon ECS

Install the Amazon ECS CLI if you haven't already done so. For more information, see Installing the Amazon ECS CLI.

Set the new Amazon ECS cluster name and Region. For example:

ECS_CLUSTER_NAME=ecs-ec2-memcached-tutorial
AWS_DEFAULT_REGION=ca-central-1

(Optional) If you don't already have an Amazon ECS cluster with the EC2 launch type where you want to install the sample Memcached workload and CloudWatch agent, you can create one by entering the following command.

ecs-cli up --capability-iam --size 1 \
--instance-type t3.medium \
--cluster $ECS_CLUSTER_NAME \
--region $AWS_REGION

The expected result of this command is as follows:

WARN[0000] You will not be able to SSH into your EC2 instances without a key pair. 
INFO[0000] Using recommended Amazon Linux 2 AMI with ECS Agent 1.44.4 and Docker version 19.03.6-ce 
INFO[0001] Created cluster                               cluster=ecs-ec2-memcached-tutorial region=ca-central-1
INFO[0002] Waiting for your cluster resources to be created... 
INFO[0002] Cloudformation stack status                   stackStatus=CREATE_IN_PROGRESS
INFO[0063] Cloudformation stack status                   stackStatus=CREATE_IN_PROGRESS
INFO[0124] Cloudformation stack status                   stackStatus=CREATE_IN_PROGRESS
VPC created: vpc-xxxxxxxxxxxxxxxxx
Security Group created: sg-xxxxxxxxxxxxxxxxx
Subnet created: subnet-xxxxxxxxxxxxxxxxx
Subnet created: subnet-xxxxxxxxxxxxxxxxx
Cluster creation succeeded.

Download the Memcached AWS CloudFormation template by entering the following command.

curl -O https://raw.githubusercontent.com/aws-samples/amazon-cloudwatch-container-insights/latest/ecs-task-definition-templates/deployment-mode/replica-service/cwagent-prometheus/sample_traffic/memcached/memcached-traffic-sample.yaml

Set the IAM role names to be created for Memcached by entering the following commands.

MEMCACHED_ECS_TASK_ROLE_NAME=memcached-prometheus-demo-ecs-task-role-name
MEMCACHED_ECS_EXECUTION_ROLE_NAME=memcached-prometheus-demo-ecs-execution-role-name

Install the sample Memcached workload by entering the following command. This sample installs the workload in host network mode.

MEMCACHED_ECS_NETWORK_MODE=host

aws cloudformation create-stack --stack-name Memcached-Prometheus-Demo-ECS-$ECS_CLUSTER_NAME-EC2-$MEMCACHED_ECS_NETWORK_MODE \
    --template-body file://memcached-traffic-sample.yaml \
    --parameters ParameterKey=ECSClusterName,ParameterValue=$ECS_CLUSTER_NAME \
                 ParameterKey=ECSNetworkMode,ParameterValue=$MEMCACHED_ECS_NETWORK_MODE \
                 ParameterKey=TaskRoleName,ParameterValue=$MEMCACHED_ECS_TASK_ROLE_NAME \
                 ParameterKey=ExecutionRoleName,ParameterValue=$MEMCACHED_ECS_EXECUTION_ROLE_NAME \
    --capabilities CAPABILITY_NAMED_IAM \
    --region $AWS_REGION

Download the latest version of cwagent-ecs-prometheus-metric-for-awsvpc.yaml by entering the following command.

curl -O https://raw.githubusercontent.com/aws-samples/amazon-cloudwatch-container-insights/latest/ecs-task-definition-templates/deployment-mode/replica-service/cwagent-prometheus/cloudformation-quickstart/cwagent-ecs-prometheus-metric-for-awsvpc.yaml

Open the file with a text editor, and find the full CloudWatch agent configuration behind the value key in the resource:CWAgentConfigSSMParameter section.

Then, in the ecs_service_discovery section, add the following configuration into the task_definition_list section.

{
    "sd_job_name": "ecs-memcached",
    "sd_metrics_ports": "9150",
    "sd_task_definition_arn_pattern": ".*:task-definition/memcached-prometheus-demo.*:[0-9]+"
},

For the metric_declaration section, the default setting does not allow any Memcached metrics. Add the following section to allow Memcached metrics. Be sure to follow the existing indentation pattern.

{
  "source_labels": ["container_name"],
  "label_matcher": "memcached-exporter-.*",
  "dimensions": [["ClusterName", "TaskDefinitionFamily"]],
  "metric_selectors": [
    "^memcached_current_(bytes|items|connections)$",
    "^memcached_items_(reclaimed|evicted)_total$",
    "^memcached_(written|read)_bytes_total$",
    "^memcached_limit_bytes$",
    "^memcached_commands_total$"
  ]
},
{
  "source_labels": ["container_name"],
  "label_matcher": "memcached-exporter-.*",
  "dimensions": [["ClusterName", "TaskDefinitionFamily","status","command"], ["ClusterName", "TaskDefinitionFamily","command"]],
  "metric_selectors": [
    "^memcached_commands_total$"
  ]
},

If you already have the CloudWatch agent deployed in the Amazon ECS cluster by AWS CloudFormation, you can create a change set by entering the following commands.

ECS_NETWORK_MODE=bridge
CREATE_IAM_ROLES=True
ECS_TASK_ROLE_NAME=your_selected_ecs_task_role_name
ECS_EXECUTION_ROLE_NAME=your_selected_ecs_execution_role_name

aws cloudformation create-change-set --stack-name CWAgent-Prometheus-ECS-${ECS_CLUSTER_NAME}-EC2-${ECS_NETWORK_MODE} \
    --template-body file://cwagent-ecs-prometheus-metric-for-bridge-host.yaml \
    --parameters ParameterKey=ECSClusterName,ParameterValue=$ECS_CLUSTER_NAME \
                 ParameterKey=CreateIAMRoles,ParameterValue=$CREATE_IAM_ROLES \
                 ParameterKey=ECSNetworkMode,ParameterValue=$ECS_NETWORK_MODE \
                 ParameterKey=TaskRoleName,ParameterValue=$ECS_TASK_ROLE_NAME \
                 ParameterKey=ExecutionRoleName,ParameterValue=$ECS_EXECUTION_ROLE_NAME \
    --capabilities CAPABILITY_NAMED_IAM \
    --region $AWS_REGION \
    --change-set-name memcached-scraping-support

Open the AWS CloudFormation console at https://console.aws.amazon.com/cloudformation.

Review the newly created changeset memcached-scraping-support. You should see one change applied to the CWAgentConfigSSMParameter resource. Execute the changeset and restart the CloudWatch agent task by entering the following commands.

aws ecs update-service --cluster $ECS_CLUSTER_NAME \
--desired-count 0 \
--service cwagent-prometheus-replica-service-EC2-$ECS_NETWORK_MODE \
--region $AWS_REGION

Wait about 10 seconds, and then enter the following command.

aws ecs update-service --cluster $ECS_CLUSTER_NAME \
--desired-count 1 \
--service cwagent-prometheus-replica-service-EC2-$ECS_NETWORK_MODE \
--region $AWS_REGION

If you are installing the CloudWatch agent with Prometheus metric collecting for the cluster for the first time, please enter the following commands:

ECS_NETWORK_MODEE=bridge
CREATE_IAM_ROLES=True
ECS_TASK_ROLE_NAME=your_selected_ecs_task_role_name
ECS_EXECUTION_ROLE_NAME=your_selected_ecs_execution_role_name

aws cloudformation create-stack --stack-name CWAgent-Prometheus-ECS-${ECS_CLUSTER_NAME}-EC2-${ECS_NETWORK_MODE} \
    --template-body file://cwagent-ecs-prometheus-metric-for-bridge-host.yaml \
    --parameters ParameterKey=ECSClusterName,ParameterValue=$ECS_CLUSTER_NAME \
                 ParameterKey=CreateIAMRoles,ParameterValue=$CREATE_IAM_ROLES \
                 ParameterKey=ECSNetworkMode,ParameterValue=$ECS_NETWORK_MODE \
                 ParameterKey=TaskRoleName,ParameterValue=$ECS_TASK_ROLE_NAME \
                 ParameterKey=ExecutionRoleName,ParameterValue=$ECS_EXECUTION_ROLE_NAME \
    --capabilities CAPABILITY_NAMED_IAM \
    --region $AWS_REGION 

Create environment variables, replacing the values below to match your deployment.

DASHBOARD_NAME=your_memcached_cw_dashboard_name
ECS_TASK_DEF_FAMILY=memcached-prometheus-demo-$ECS_CLUSTER_NAME-EC2-$MEMCACHED_ECS_NETWORK_MOD

Enter the following command to create the dashboard.

curl https://raw.githubusercontent.com/aws-samples/amazon-cloudwatch-container-insights/latest/ecs-task-definition-templates/deployment-mode/replica-service/cwagent-prometheus/sample_cloudwatch_dashboards/memcached/cw_dashboard_memcached.json \
| sed "s/{{YOUR_AWS_REGION}}/$AWS_REGION/g" \
| sed "s/{{YOUR_CLUSTER_NAME}}/$ECS_CLUSTER_NAME/g" \
| sed "s/{{YOUR_TASK_DEF_FAMILY}}/$ECS_TASK_DEF_FAMILY/g" \
| xargs -0 aws cloudwatch put-dashboard --dashboard-name ${DASHBOARD_NAME} --region $AWS_REGION --dashboard-body