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CloudWatch Dashboards

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CloudWatch Dashboards

CloudWatch Dashboards create customizable views of your metrics and logs. You can build operational dashboards for SREs, business dashboards for stakeholders, and share them across accounts.

Dashboard Concepts

Widget Types

WidgetUse
LineTime-series metrics (CPU, latency)
Stacked AreaMultiple metrics stacked (request count by status code)
BarComparative metrics (error rate by service)
NumberSingle metric value (current p99 latency)
TextStatic text, markdown (annotations, team info)
Pie/DonutPercentage breakdown (error types)

Dashboard Structure

{
  "widgets": [
    {
      "type": "metric",
      "x": 0, "y": 0, "width": 12, "height": 6,
      "properties": {
        "title": "API Latency",
        "metrics": [
          ["AWS/ApplicationELB", "TargetResponseTime", "LoadBalancer", "app/my-alb"],
          [".", "HealthyHostCount", ".", "."]
        ],
        "period": 60,
        "stat": "Average",
        "view": "timeSeries"
      }
    },
    {
      "type": "text",
      "x": 12, "y": 0, "width": 12, "height": 3,
      "properties": {
        "markdown": "# Production Dashboard\nLast updated: 2024-01-15"
      }
    }
  ]
}

Creating Dashboards

Via Console

Console: CloudWatch → Dashboards → Create dashboard

Via AWS CLI

aws cloudwatch put-dashboard \
  --dashboard-name production-overview \
  --dashboard-body '{
    "widgets": [
      {
        "type": "metric",
        "properties": {
          "title": "CPU Utilization",
          "metrics": [["AWS/EC2","CPUUtilization"]],
          "period": 300,
          "stat": "Average"
        }
      }
    ]
  }'

Via CloudFormation

Resources:
  Dashboard:
    Type: AWS::CloudWatch::Dashboard
    Properties:
      DashboardName: production-overview
      DashboardBody: !Sub |
        {
          "widgets": [
            {
              "type": "metric",
              "properties": {
                "title": "CPU Utilization",
                "metrics": [["AWS/EC2","CPUUtilization",{"value": "*"}]],
                "period": 300,
                "stat": "Average"
              }
            }
          ]
        }

Dashboard Features

Live Data

Enable “Live Data” to show real-time metrics (refreshes every 10 seconds). Useful for monitoring active incidents.

Annotations

Add vertical lines for significant events (deployments, incidents):

{
  "type": "metric",
  "properties": {
    "annotations": {
      "horizontal": [
        {
          "label": "Deployment",
          "value": 1642233600
        }
      ]
    }
  }
}

Metric Math on Dashboards

Use metric math expressions directly in dashboard widgets:

{
  "type": "metric",
  "properties": {
    "title": "Error Rate %",
    "metrics": [
      {"expression": "100 * (m1/m2)", "label": "Error Rate"}
    ]
  }
}

Cross-Service Dashboards

ALB + EC2 + RDS Dashboard

{
  "widgets": [
    {
      "type": "metric", "x": 0, "y": 0, "width": 12, "height": 6,
      "properties": {
        "title": "ALB Metrics",
        "metrics": [
          ["AWS/ApplicationELB", "RequestCount", "LoadBalancer", "app/my-alb"],
          [".", "TargetResponseTime", ".", "."],
          [".", "UnHealthyHostCount", ".", "."]
        ]
      }
    },
    {
      "type": "metric", "x": 12, "y": 0, "width": 12, "height": 6,
      "properties": {
        "title": "EC2 Metrics",
        "metrics": [
          ["AWS/EC2", "CPUUtilization", {"value": "*"}],
          ["AWS/EC2", "NetworkOut", {"value": "*"}]
        ]
      }
    },
    {
      "type": "metric", "x": 0, "y": 6, "width": 12, "height": 6,
      "properties": {
        "title": "RDS Metrics",
        "metrics": [
          ["AWS/RDS", "DatabaseConnections", "DBInstanceIdentifier", "my-db"],
          [".", "CPUUtilization", ".", "."],
          [".", "FreeStorageSpace", ".", "."]
        ]
      }
    }
  ]
}

Cross-Account Dashboards

CloudWatch cross-account dashboards aggregate metrics from multiple AWS accounts:

Management Account (Observability account)
  └── CloudWatch Dashboard (cross-account view)
        ← /aws/lambda/app (Account A)
        ← /aws/lambda/api (Account B)
        ← /aws/ec2/fleet (Account C)

Configuration

# In the monitoring account
aws cloudwatch put-dashboard \
  --dashboard-name cross-account-prod \
  --dashboard-body '...'
 
# Widget with cross-account dimension
{
  "type": "metric",
  "properties": {
    "metrics": [
      ["AWS/Lambda", "Invocations", "FunctionName", "my-function", "Account", "111122223333"]
    ]
  }
}

Automatic Dashboards

CloudWatch can auto-generate service-level dashboards:

  • EC2: CPU, network, disk for all instances
  • RDS: Connections, CPU, storage, replication lag
  • Lambda: Invocations, duration, errors, throttles
  • ALB: Request count, latency, unhealthy hosts

Widget Syncing

Dashboard widgets can sync to a specific time range — when you zoom in on one widget, all other widgets update to the same time range. Enable “Synced” in the widget settings.

Limits

ResourceLimit
Dashboards per account100
Widgets per dashboard100
Metrics per widget100
Dashboard body size512KB

References

Pricing Examples

Scenario 1: A startup’s SRE team building a production dashboard with 20 widgets (CPU, memory, latency, errors per service, 10 services × 2 widgets each). Dashboards are free (you only pay for the underlying metrics). Total: $0/month for the dashboard itself.

Scenario 2: A multi-account enterprise with 5 member accounts sharing dashboards from a central monitoring account. Each account has 50 custom metrics. CloudWatch charges 0.30 = $75/month. Without a central dashboard, each team manages their own — chaos.

Nuggets & Gotchas

  • Dashboard widgets without a time range show the last 3 hours by default — not 24 hours: When you create a widget, it inherits the dashboard’s time range. If the dashboard has no default, widgets default to 3 hours. Always set an explicit default time range for operational dashboards.
  • Metric math expressions in widgets are evaluated at display time — not stored: If you use SEARCH() in a dashboard metric math expression, it re-evaluates every time the dashboard loads. This can be slow for complex searches and may hit API rate limits on high-frequency refresh.
  • Cross-account dashboards require the cloudwatch:CrossAccountLink permission in the monitoring account: If you create a cross-account dashboard and see no data, check that the member accounts have granted the monitoring account cloudwatch:CrossAccountLink via the CloudWatch cross-account settings.
  • Auto-refresh on dashboards has a minimum of 10 seconds: You cannot set auto-refresh faster than 10 seconds. For real-time monitoring (faster than 10 seconds), use a third-party tool or direct CloudWatch API polling.
  • Dashboard JSON has a 512KB limit — complex dashboards may exceed this: If you hit this limit, split into multiple dashboards (one per service) and use a “dashboard of dashboards” text widget to link them.

Graph View