YACE - yet another cloudwatch exporter

What is this organisation?

Medium Article about rebranding yace

Project Status

YACE is currently in quick iteration mode. Things will probably break in upcoming versions. However, it has been in production use at InVision AG for a couple of months already.

Security

Supported Versions

Only latest version gets security updates. We won't support older versions.

Reporting a Vulnerability

In case of a vulnerability please directly contact us via mail - security@nerdswords.de

Do not disclose any specifics in github issues! - Thank you.

We will contact you as soon as possible.

Features

• Stop worrying about your AWS IDs - Auto discovery of resources via tags

• Structured JSON logging

• Filter monitored resources via regex

• Automatic adding of tag labels to metrics

• Automatic adding of dimension labels to metrics

• Allows to export 0 even if CloudWatch returns nil

• Allows exports metrics with CloudWatch timestamps (disabled by default)

• Static metrics support for all cloudwatch metrics without auto discovery

• Pull data from multiple AWS accounts using cross-account roles

• Supported services with auto discovery through tags:

  • acm (AWS/CertificateManager) - Certificate Manager
  • alb (AWS/ApplicationELB) - Application Load Balancer
  • apigateway (AWS/ApiGateway) - API Gateway
  • appsync (AWS/AppSync) - AppSync
  • athena (AWS/Athena) - Athena
  • billing (AWS/Billing) - Billing
  • cassandra (AWS/Cassandra) - Cassandra
  • cloudfront (AWS/CloudFront) - Cloud Front
  • cognito-idp (AWS/Cognito) - Cognito
  • docdb (AWS/DocDB) - DocumentDB (with MongoDB compatibility)
  • dynamodb (AWS/DynamoDB) - NoSQL Key-Value Database
  • ebs (AWS/EBS) - Elastic Block Storage
  • ec (AWS/Elasticache) - ElastiCache
  • ec2 (AWS/EC2) - Elastic Compute Cloud
  • ec2Spot (AWS/EC2Spot) - Elastic Compute Cloud for Spot Instances
  • ecs-svc (AWS/ECS) - Elastic Container Service (Service Metrics)
  • ecs-containerinsights (ECS/ContainerInsights) - ECS/ContainerInsights (Fargate metrics)
  • efs (AWS/EFS) - Elastic File System
  • elb (AWS/ELB) - Elastic Load Balancer
  • emr (AWS/ElasticMapReduce) - Elastic MapReduce
  • es (AWS/ES) - ElasticSearch
  • fsx (AWS/FSx) - FSx File System
  • gamelift (AWS/GameLift) - GameLift
  • glue (Glue) - AWS Glue Jobs
  • iot (AWS/IoT) - IoT
  • kinesis (AWS/Kinesis) - Kinesis Data Stream
  • nfw (AWS/NetworkFirewall) - Network Firewall
  • ngw (AWS/NATGateway) - NAT Gateway
  • lambda (AWS/Lambda) - Lambda Functions
  • mq (AWS/AmazonMQ) - Managed Message Broker Service
  • neptune (AWS/Neptune) - Neptune
  • nlb (AWS/NetworkELB) - Network Load Balancer
  • redshift (AWS/Redshift) - Redshift Database
  • rds (AWS/RDS) - Relational Database Service
  • r53r (AWS/Route53Resolver) - Route53 Resolver
  • s3 (AWS/S3) - Object Storage
  • ses (AWS/SES) - Simple Email Service
  • shield (AWS/DDoSProtection) - Distributed Denial of Service (DDoS) protection service
  • sqs (AWS/SQS) - Simple Queue Service
  • tgw (AWS/TransitGateway) - Transit Gateway
  • vpn (AWS/VPN) - VPN connection
  • asg (AWS/AutoScaling) - Auto Scaling Group
  • kafka (AWS/Kafka) - Managed Apache Kafka
  • firehose (AWS/Firehose) - Managed Streaming Service
  • sns (AWS/SNS) - Simple Notification Service
  • sfn (AWS/States) - Step Functions
  • wafv2 (AWS/WAFV2) - Web Application Firewall v2
  • workspaces (AWS/WorkSpaces) - Workspaces

Image

• ghcr.io/nerdswords/yet-another-cloudwatch-exporter:x.x.x e.g. 0.5.0
• See Releases for binaries

Configuration

Command Line Options

Option	Description
labels-snake-case	Causes labels on metrics to be output in snake case instead of camel case
floating-time-window	Use a floating start/end time window instead of rounding times to 5 min intervals

Top level configuration

Key	Description
discovery	Auto-discovery configuration
static	List of static configurations

Auto-discovery configuration

Key	Description
exportedTagsOnMetrics	List of tags per service to export to all metrics
jobs	List of auto-discovery jobs

exportedTagsOnMetrics example:

exportedTagsOnMetrics:
  ec2:
    - Name
    - type

Note: Only tagged resources are discovered.

Auto-discovery job

Key	Description
regions	List of AWS regions
type	Cloudwatch service alias ("alb", "ec2", etc) or namespace name ("AWS/EC2", "AWS/S3", etc).
length (Default 120)	How far back to request data for in seconds
delay	If set it will request metrics up until current_time - delay
roles	List of IAM roles to assume (optional)
searchTags	List of Key/Value pairs to use for tag filtering (all must match), Value can be a regex.
period	Statistic period in seconds (General Setting for all metrics in this job)
addCloudwatchTimestamp	Export the metric with the original CloudWatch timestamp (General Setting for all metrics in this job)
customTags	Custom tags to be added as a list of Key/Value pairs
metrics	List of metric definitions

searchTags example:

searchTags:
  - key: env
    value: production

Metric definition

Key	Description
name	CloudWatch metric name
statistics	List of statistic types, e.g. "Minimum", "Maximum", etc.
period	Statistic period in seconds (Overrides job level setting)
length	How far back to request data for in seconds(for static jobs)
delay	If set it will request metrics up until current_time - delay(for static jobs)
nilToZero	Return 0 value if Cloudwatch returns no metrics at all. By default NaN will be reported
addCloudwatchTimestamp	Export the metric with the original CloudWatch timestamp (Overrides job level setting)

• Available statistics: Maximum, Minimum, Sum, SampleCount, Average, pXX.
• Watch out using addCloudwatchTimestamp for sparse metrics, e.g from S3, since Prometheus won't scrape metrics containing timestamps older than 2-3 hours
• Setting Inheritance: Some settings at the job level are overridden by settings at the metric level. This allows for a specific setting to override a general setting. The currently inherited settings are period, and addCloudwatchTimestamp

Static configuration

Key	Description
regions	List of AWS regions
roles	List of IAM roles to assume
namespace	CloudWatch namespace
name	Must be set with multiple block definitions per namespace
customTags	Custom tags to be added as a list of Key/Value pairs
dimensions	CloudWatch metric dimensions as a list of Name/Value pairs
metrics	List of metric definitions

Example of config File

discovery:
  exportedTagsOnMetrics:
    ec2:
      - Name
    ebs:
      - VolumeId
  jobs:
  - type: es
    regions:
      - eu-west-1
    searchTags:
      - key: type
        value: ^(easteregg|k8s)$
    metrics:
      - name: FreeStorageSpace
        statistics:
        - Sum
        period: 600
        length: 60
      - name: ClusterStatus.green
        statistics:
        - Minimum
        period: 600
        length: 60
      - name: ClusterStatus.yellow
        statistics:
        - Maximum
        period: 600
        length: 60
      - name: ClusterStatus.red
        statistics:
        - Maximum
        period: 600
        length: 60
  - type: elb
    regions:
      - eu-west-1
    length: 900
    delay: 120
    searchTags:
      - key: KubernetesCluster
        value: production-19
    metrics:
      - name: HealthyHostCount
        statistics:
        - Minimum
        period: 600
        length: 600 #(this will be ignored)
      - name: HTTPCode_Backend_4XX
        statistics:
        - Sum
        period: 60
        length: 900 #(this will be ignored)
        delay: 300 #(this will be ignored)
        nilToZero: true
  - type: alb
    regions:
      - eu-west-1
    searchTags:
      - key: kubernetes.io/service-name
        value: .*
    metrics:
      - name: UnHealthyHostCount
        statistics: [Maximum]
        period: 60
        length: 600
  - type: vpn
    regions:
      - eu-west-1
    searchTags:
      - key: kubernetes.io/service-name
        value: .*
    metrics:
      - name: TunnelState
        statistics:
        - p90
        period: 60
        length: 300
  - type: kinesis
    regions:
      - eu-west-1
    metrics:
      - name: PutRecords.Success
        statistics:
        - Sum
        period: 60
        length: 300
  - type: s3
    regions:
      - eu-west-1
    searchTags:
      - key: type
        value: public
    metrics:
      - name: NumberOfObjects
        statistics:
          - Average
        period: 86400
        length: 172800
      - name: BucketSizeBytes
        statistics:
          - Average
        period: 86400
        length: 172800
  - type: ebs
    regions:
      - eu-west-1
    searchTags:
      - key: type
        value: public
    metrics:
      - name: BurstBalance
        statistics:
        - Minimum
        period: 600
        length: 600
        addCloudwatchTimestamp: true
  - type: kafka
    regions:
      - eu-west-1
    searchTags:
      - key: env
        value: dev
    metrics:
      - name: BytesOutPerSec
        statistics:
        - Average
        period: 600
        length: 600
static:
  - namespace: AWS/AutoScaling
    name: must_be_set
    regions:
      - eu-west-1
    dimensions:
     - name: AutoScalingGroupName
       value: Test
    customTags:
      - key: CustomTag
        value: CustomValue
    metrics:
      - name: GroupInServiceInstances
        statistics:
        - Minimum
        period: 60
        length: 300

[Source: config_test.yml]

Metrics Examples

### Metrics with exportedTagsOnMetrics
aws_ec2_cpuutilization_maximum{dimension_InstanceId="i-someid", name="arn:aws:ec2:eu-west-1:472724724:instance/i-someid", tag_Name="jenkins"} 57.2916666666667

### Info helper with tags
aws_elb_info{name="arn:aws:elasticloadbalancing:eu-west-1:472724724:loadbalancer/a815b16g3417211e7738a02fcc13bbf9",tag_KubernetesCluster="production-19",tag_Name="",tag_kubernetes_io_cluster_production_19="owned",tag_kubernetes_io_service_name="nginx-ingress/private-ext",region="eu-west-1"} 0
aws_ec2_info{name="arn:aws:ec2:eu-west-1:472724724:instance/i-someid",tag_Name="jenkins"} 0

### Track cloudwatch requests to calculate costs
yace_cloudwatch_requests_total 168

Query Examples without exportedTagsOnMetrics

# CPUUtilization + Name tag of the instance id - No more instance id needed for monitoring
aws_ec2_cpuutilization_average + on (name) group_left(tag_Name) aws_ec2_info

# Free Storage in Megabytes + tag Type of the elasticsearch cluster
(aws_es_free_storage_space_sum + on (name) group_left(tag_Type) aws_es_info) / 1024

# Add kubernetes / kops tags on 4xx elb metrics
(aws_elb_httpcode_backend_4_xx_sum + on (name) group_left(tag_KubernetesCluster,tag_kubernetes_io_service_name) aws_elb_info)

# Availability Metric for ELBs (Successful requests / Total Requests) + k8s service name
# Use nilToZero on all metrics else it won't work
((aws_elb_request_count_sum - on (name) group_left() aws_elb_httpcode_backend_4_xx_sum) - on (name) group_left() aws_elb_httpcode_backend_5_xx_sum) + on (name) group_left(tag_kubernetes_io_service_name) aws_elb_info

# Forecast your elasticsearch disk size in 7 days and report metrics with tags type and version
predict_linear(aws_es_free_storage_space_minimum[2d], 86400 * 7) + on (name) group_left(tag_type, tag_version) aws_es_info

# Forecast your cloudwatch costs for next 32 days based on last 10 minutes
# 1.000.000 Requests free
# 0.01 Dollar for 1.000 GetMetricStatistics Api Requests (https://aws.amazon.com/cloudwatch/pricing/)
((increase(yace_cloudwatch_requests_total[10m]) * 6 * 24 * 32) - 100000) / 1000 * 0.01

IAM

The following IAM permissions are required for YACE to work.

"tag:GetResources",
"cloudwatch:GetMetricData",
"cloudwatch:GetMetricStatistics",
"cloudwatch:ListMetrics"

The following IAM permissions are required for the transit gateway attachment (tgwa) metrics to work.

"ec2:DescribeTags",
"ec2:DescribeInstances",
"ec2:DescribeRegions",
"ec2:DescribeTransitGateway*"

The following IAM permission is required to discover tagged API Gateway REST APIs:

"apigateway:GET"

Running locally

docker run -d --rm -v $PWD/credentials:/exporter/.aws/credentials -v $PWD/config.yml:/tmp/config.yml \
-p 5000:5000 --name yace ghcr.io/nerdswords/yet-another-cloudwatch-exporter:vx.xx.x # release version as tag - Do not forget the version 'v'

Kubernetes Installation

---
apiVersion: v1
kind: ConfigMap
metadata:
  name: yace
data:
  config.yml: |-
    ---
    # Start of config file
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: yace
spec:
  replicas: 1
  selector:
    matchLabels:
      name: yace
  template:
    metadata:
      labels:
        name: yace
    spec:
      containers:
      - name: yace
        image: ghcr.io/nerdswords/yet-another-cloudwatch-exporter:vx.x.x # release version as tag - Do not forget the version 'v'
        imagePullPolicy: IfNotPresent
        args:
          - "--config.file=/tmp/config.yml"
        ports:
        - name: app
          containerPort: 5000
        volumeMounts:
        - name: config-volume
          mountPath: /tmp
      volumes:
      - name: config-volume
        configMap:
          name: yace

Options

RoleArns

Multiple roleArns are useful, when you are monitoring multi-account setup, where all accounts are using same AWS services. For example, you are running yace in monitoring account and you have number of accounts (for example newspapers, radio and television) running ECS clusters. Each account gives yace permissions to assume local IAM role, which has all the necessary permissions for Cloudwatch metrics. On this kind of setup, you could simply list:

  jobs:
    - type: ecs-svc
      regions:
        - eu-north-1
      roles:
        - roleArn: "arn:aws:iam:1111111111111:role/prometheus" # newspaper
        - roleArn: "arn:aws:iam:2222222222222:role/prometheus" # radio
        - roleArn: "arn:aws:iam:3333333333333:role/prometheus" # television
      metrics:
        - name: MemoryReservation
          statistics:
            - Average
            - Minimum
            - Maximum
          period: 600
          length: 600

Additionally, if the IAM role you want to assume requires an External ID you can specify it this way:

  roles:
    - roleArn: "arn:aws:iam:1111111111111:role/prometheus"
      externalId: "shared-external-identifier"

Requests concurrency

The flags 'cloudwatch-concurrency' and 'tag-concurrency' define the number of concurrent request to cloudwatch metrics and tags. Their default value is 5.

Setting a higher value makes faster scraping times but can incur in throttling and the blocking of the API.

Decoupled scraping

The flag 'decoupled-scraping' makes the exporter to scrape Cloudwatch metrics in background in fixed intervals, in stead of each time that the '/metrics' endpoint is fetched. This protects from the abuse of API requests that can cause extra billing in AWS account. This flag is activated by default.

If the flag 'decoupled-scraping' is activated, the flag 'scraping-interval' defines the seconds between scrapes. Its default value is 300.

Troubleshooting / Debugging

Help my metrics are intermittent

• Please, try out a bigger length e.g. for elb try out a length of 600 and a period of 600. Then test how low you can go without losing data. ELB metrics on AWS are written every 5 minutes (300) in default.

My metrics only show new values after 5 minutes

• Please, try to set a lower value for the 'scraping-interval' flag or set the 'decoupled-scraping' to false.

Contribute

Development Setup / Guide

Thank you

• Justin Santa Barbara - For telling me about AWS tags api which simplified a lot - Thanks!
• Brian Brazil - Who gave a lot of feedback regarding UX and prometheus lib - Thanks!