8
6

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?

More than 5 years have passed since last update.

[JAWS-UG CLI] CloudWatch:#3 DynamoDBのアラーム設定 (ReadCapacity)

Posted at

https://jawsug-cli.doorkeeper.jp/events/20523 でのハンズオン資料です。

AWS CLIを利用して、DynamoDBテーブルの「プロビジョニングされたスループット」の使用量が閾値に達したときに通知する設定を行ってみます。

参考: http://docs.aws.amazon.com/ja_jp/AmazonCloudWatch/latest/DeveloperGuide/dynamo-metricscollected.html

マネジメントコンソールでのテーブル作成時、Thrughput Alarmsの設定で80%を指定した場合のサンプルになります。

一定期間の期間内(period * evaluation-periods = この設定では60分後)に
データのputやgetが無いと、INSUFFICIENT_DATAになる(OKにならなくなる)ようです。

前提条件

CloudWatchへの権限

CloudWatchに対して以下の権限があること。
(今回のハンズオンでは使わない権限もあります。)

      {
        "Version": "2012-10-17",
        "Statement": [
          {
            "Action": [
              "cloudwatch:DescribeAlarmHistory",
              "cloudwatch:DescribeAlarms",
              "cloudwatch:DescribeAlarmsForMetric",
              "cloudwatch:GetMetricStatistics",
              "cloudwatch:ListMetrics",
              "cloudwatch:PutMetricAlarm",
              "cloudwatch:SetAlarmState",
            ],
            "Effect": "Allow",
            "Resource": "*"
          }
        ]
      }

AWS CLIのバージョン

以下のバージョンで動作確認済

  • AWS CLI 1.7.18
  • AWS CLI 1.7.8
コマンド
aws --version
結果(例)
aws-cli/1.7.18 Python/2.7.5 Darwin/13.4.0
  1. 準備
    =======

0.1. リージョンの決定

作成するユーザのデフォルトリージョンを決めます。
(カレントユーザが利用するカレントリージョンも切り変わります。)

コマンド(東京リージョンの場合)
export AWS_DEFAULT_REGION='ap-northeast-1'

0.2. 変数の確認

プロファイルとリージョンが想定のものになっていることを確認します。

変数の確認
aws configure list
結果(例)
            Name                    Value             Type    Location
            ----                    -----             ----    --------
         profile      iam_full-prjZ-mbp13              env    AWS_DEFAULT_PROFILE
      access_key     ****************LOAQ shared-credentials-file
      secret_key     ****************I1O1 shared-credentials-file
          region           ap-northeast-1              env    AWS_DEFAULT_REGION
  1. 事前作業
    ===========

1.1. 変数の確認

変数の確認
cat << ETX

DYNAMO_TABLE_NAME:  ${DYNAMO_TABLE_NAME}
SNS_TOPIC_ARN:      ${SNS_TOPIC_ARN}

ETX

1.2. DynamoDBテーブル名の指定

DYNAMO_TABLE_NAMEが空か、想定と異なる場合は指定しなおします。

コマンド(例)
DYNAMO_TABLE_NAME='Thread'

1.3. 通知先SNSの決定

SNS_TOPIC_NAMEが空か、想定と異なる場合は指定しなおします。

コマンド
SNS_TOPIC_NAME='dynamodb'
  • SNSトピックのARN取得
コマンド
SNS_TOPIC_ARN=`aws sns list-topics | jq -r .Topics[].TopicArn | grep ${SNS_TOPIC_NAME}` \
  && echo ${SNS_TOPIC_ARN}

1.4. 変数の確認 (再)

変数の確認
cat << ETX

DYNAMO_TABLE_NAME:  ${DYNAMO_TABLE_NAME}
SNS_TOPIC_ARN:      ${SNS_TOPIC_ARN}

ETX
  1. メトリックの確認 (テーブルに入出力があった場合)
    ===================

Note: テーブル作成後、一覧表示されるまで15分ほど必要になるようです。

2.1. 名前空間、ディメンションの指定

コマンド
CWATCH_NAMESPACE='AWS/DynamoDB'
CWATCH_DIMENSIONS="Name=TableName,Value=${DYNAMO_TABLE_NAME}"

2.2. 一覧の取得

入力値の確認をします。

変数確認
cat << ETX

      CWATCH_NAMESPACE:  ${CWATCH_NAMESPACE}
      CWATCH_DIMENSIONS: ${CWATCH_DIMENSIONS}

ETX
コマンド
aws cloudwatch list-metrics \
        --namespace ${CWATCH_NAMESPACE} \
        --dimensions ${CWATCH_DIMENSIONS}
結果(例)
      {
        "Metrics": [
          {
              "Namespace": "AWS/DynamoDB",
              "Dimensions": [
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "MetricName": "ProvisionedReadCapacityUnits"
          },
          {
              "Namespace": "AWS/DynamoDB",
              "Dimensions": [
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "MetricName": "ProvisionedWriteCapacityUnits"
          },
          {
              "Namespace": "AWS/DynamoDB",
              "Dimensions": [
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "MetricName": "ConsumedReadCapacityUnits"
          },
          {
              "Namespace": "AWS/DynamoDB",
              "Dimensions": [
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "MetricName": "ConsumedWriteCapacityUnits"
          },
          {
              "Namespace": "AWS/DynamoDB",
              "Dimensions": [
                  {
                      "Name": "Operation",
                      "Value": "PutItem"
                  },
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "MetricName": "SuccessfulRequestLatency"
          },
          {
              "Namespace": "AWS/DynamoDB",
              "Dimensions": [
                  {
                      "Name": "Operation",
                      "Value": "Scan"
                  },
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "MetricName": "SuccessfulRequestLatency"
          },
          {
              "Namespace": "AWS/DynamoDB",
              "Dimensions": [
                  {
                      "Name": "Operation",
                      "Value": "Scan"
                  },
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "MetricName": "ReturnedItemCount"
          }
        ]
      }
  1. CloudWatchアラームの設定 (ReadCapacity)
    ===========

3.1. スループットの指定

コマンド(例)
DYNAMO_READ_UNIT='10'

3.2. アラーム名(その概要)の指定

コマンド
CWATCH_ALARM_NAME="${DYNAMO_TABLE_NAME}-ReadCapacityUnitsLimit-BasicAlarm"
CWATCH_ALARM_DESC="Read Capacity Units Limit Basic Alarm for ${DYNAMO_TABLE_NAME}"

3.3. メトリックの指定

名前空間:
AWS/DynamoDB

ディメンション:
テーブル名

メトリック名:
ConsumedWriteCapacityUnits

メトリック単位:
Count

統計方法:
Sum

コマンド
CWATCH_NAMESPACE='AWS/DynamoDB'
CWATCH_DIMENSIONS="Name=TableName,Value=${DYNAMO_TABLE_NAME}"
CWATCH_METRIC_NAME='ConsumedReadCapacityUnits'
CWATCH_METRIC_UNIT='Count'
CWATCH_STATISTICS='Sum'

3.4. アラーム設定値の指定

閾値:
80%

監視周期:
300秒

評価期間:
12周期 (300秒x12回=1時間)

比較方法:
閾値以上

コマンド
DYNAMO_READ_RATE='80'
CWATCH_ALARM_PERIOD='300'
CWATCH_EVALUATION_PERIOD='12'
CWATCH_COMPARISON='GreaterThanOrEqualToThreshold'

3.5. アラーム閾値の算出

コマンド
CWATCH_THRESHOLD=`echo "scale=1; ${CWATCH_ALARM_PERIOD} * ${DYNAMO_READ_UNIT} * ${DYNAMO_READ_RATE}/100;" | bc`;
      echo ${CWATCH_THRESHOLD}

3.6. アラーム通知先

コマンド
CWATCH_ALARM_TOPIC=${SNS_TOPIC_ARN}

3.7. アラームの作成

変数の確認

cat << ETX

        CWATCH_NAMESPACE:         ${CWATCH_NAMESPACE}
        CWATCH_METRIC_NAME:       ${CWATCH_METRIC_NAME}
        CWATCH_METRIC_UNIT:       ${CWATCH_METRIC_UNIT}
        CWATCH_STATISTICS:        ${CWATCH_STATISTICS}
        CWATCH_DIMENSIONS:        ${CWATCH_DIMENSIONS}
        CWATCH_ALARM_PERIOD:      ${CWATCH_ALARM_PERIOD}
        CWATCH_EVALUATION_PERIOD: ${CWATCH_EVALUATION_PERIOD}
        CWATCH_THRESHOLD:         ${CWATCH_THRESHOLD}
        CWATCH_COMPARISON:        ${CWATCH_COMPARISON}
        CWATCH_ALARM_NAME:        ${CWATCH_ALARM_NAME}
        CWATCH_ALARM_DESC:       "${CWATCH_ALARM_DESC}"
        CWATCH_ALARM_TOPIC:       ${CWATCH_ALARM_TOPIC}

ETX
command
aws cloudwatch put-metric-alarm \
        --namespace           ${CWATCH_NAMESPACE} \
        --metric-name         ${CWATCH_METRIC_NAME} \
        --unit                ${CWATCH_METRIC_UNIT} \
        --statistic           ${CWATCH_STATISTICS} \
        --dimensions          ${CWATCH_DIMENSIONS} \
        --period              ${CWATCH_ALARM_PERIOD} \
        --evaluation-periods  ${CWATCH_EVALUATION_PERIOD} \
        --threshold           ${CWATCH_THRESHOLD} \
        --comparison-operator ${CWATCH_COMPARISON} \
        --alarm-name          ${CWATCH_ALARM_NAME} \
        --alarm-description  "${CWATCH_ALARM_DESC}" \
        --alarm-actions       ${CWATCH_ALARM_TOPIC}
result
      (戻り値なし)

3.8. アラームの確認

コマンド
aws cloudwatch describe-alarms --alarm-names ${CWATCH_ALARM_NAME}
結果(例)
      {
        "MetricAlarms": [
          {
              "EvaluationPeriods": 12,
              "AlarmArn": "arn:aws:cloudwatch:us-west-2:XXXXXXXXXXXX:alarm:ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm",
              "StateUpdatedTimestamp": "2015-02-15T07:24:06.461Z",
              "AlarmConfigurationUpdatedTimestamp": "2015-02-15T07:23:28.223Z",
              "ComparisonOperator": "GreaterThanOrEqualToThreshold",
              "AlarmActions": [
                  "arn:aws:sns:us-west-2:XXXXXXXXXXXX:dynamodb"
              ],
              "Namespace": "AWS/DynamoDB",
              "AlarmDescription": "Read Capacity Units Limit Basic Alarm for ProductCatalog",
              "StateReasonData": "{\"version\":\"1.0\",\"queryDate\":\"2015-02-15T07:24:06.455+0000\",\"unit\":\"Count\",\"statistic\":\"Sum\",\"period\":300,\"recentDatapoints\":[],\"threshold\":2400.0}",
              "Period": 300,
              "StateValue": "INSUFFICIENT_DATA",
              "Threshold": 2400.0,
              "AlarmName": "ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm",
              "Dimensions": [
                  {
                      "Name": "TableName",
                      "Value": "ProductCatalog"
                  }
              ],
              "Unit": "Count",
              "Statistic": "Sum",
              "StateReason": "Unchecked: Initial alarm creation",
              "InsufficientDataActions": [],
              "OKActions": [],
              "ActionsEnabled": true,
              "MetricName": "ConsumedReadCapacityUnits"
          }
        ]
      }

3.9. historyの確認

コマンド
CWATCH_MAX_ITEMS='2'
コマンド
aws cloudwatch describe-alarm-history \
        --alarm-name ${CWATCH_ALARM_NAME} \
        --max-items ${CWATCH_MAX_ITEMS}
結果(例)
      {
        "AlarmHistoryItems": [
          {
              "Timestamp": "2015-02-14T06:37:59.453Z",
              "HistoryItemType": "StateUpdate",
              "AlarmName": "ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm",
              "HistoryData": "{\"version\":\"1.0\",\"oldState\":{\"stateValue\":\"INSUFFICIENT_DATA\",\"stateReason\":\"Unchecked: Initial alarm creation\"},\"newState\":{\"stateValue\":\"OK\",\"stateReason\":\"Threshold Crossed: 1 datapoint (8.0) was not greater than or equal to the threshold (240.0).\",\"stateReasonData\":{\"version\":\"1.0\",\"queryDate\":\"2015-02-14T06:37:59.447+0000\",\"startDate\":\"2015-02-14T06:22:00.000+0000\",\"unit\":\"Count\",\"statistic\":\"Sum\",\"period\":300,\"recentDatapoints\":[8.0],\"threshold\":240.0}}}",
              "HistorySummary": "Alarm updated from INSUFFICIENT_DATA to OK"

          },
          {
              "Timestamp": "2015-02-14T06:37:58.808Z",
              "HistoryItemType": "ConfigurationUpdate",
              "AlarmName": "ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm",
              "HistoryData": "{\"version\":\"1.0\",\"type\":\"Create\",\"createdAlarm\":{\"threshold\":240.0,\"stateValue\":\"INSUFFICIENT_DATA\",\"metricName\":\"ConsumedReadCapacityUnits\",\"period\":300,\"dimensions\":[{\"name\":\"TableName\",\"value\":\"ProductCatalog\"}],\"alarmName\":\"ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\",\"unit\":\"Count\",\"actionsEnabled\":true,\"okactions\":[],\"alarmActions\":[\"arn:aws:sns:us-west-2:XXXXXXXXXXXX:dynamodb\"],\"namespace\":\"AWS/DynamoDB\",\"evaluationPeriods\":12,\"comparisonOperator\":\"GreaterThanOrEqualToThreshold\",\"statistic\":\"Sum\",\"alarmArn\":\"arn:aws:cloudwatch:us-west-2:XXXXXXXXXXXX:alarm:ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\",\"insufficientDataActions\":[],\"alarmDescription\":\"Read Capacity Units Limit Basic Alarm for ProductCatalog",\"alarmConfigurationUpdatedTimestamp\":\"2015-02-14T06:37:58.808+0000\",\"stateUpdatedTimestamp\":\"2015-02-14T06:37:58.808+0000\"}}",
              "HistorySummary": "Alarm \"ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\" created"
          }
        ]
      }

3.10. アラームの送信テスト

コマンド
CWATCH_STATE_VALUE='ALARM'
CWATCH_STATE_REASON='test alarm.'
command
aws cloudwatch set-alarm-state \
        --alarm-name ${CWATCH_ALARM_NAME} \
        --state-value ${CWATCH_STATE_VALUE} \
        --state-reason "${CWATCH_STATE_REASON}"
result
      (戻り値なし)

3.11. historyの確認

コマンド
CWATCH_MAX_ITEMS='3'
コマンド
aws cloudwatch describe-alarm-history \
        --alarm-name ${CWATCH_ALARM_NAME} \
        --max-items ${CWATCH_MAX_ITEMS}
結果(例)
      {
        "AlarmHistoryItems": [
          {
              "Timestamp": "2015-02-14T06:45:27.209Z",
              "HistoryItemType": "StateUpdate",
              "AlarmName": "ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm",
              "HistoryData": "{\"version\":\"1.0\",\"oldState\":{\"stateValue\":\"ALARM\",\"stateReason\":\"test alarm.\"},\"newState\":{\"stateValue\":\"OK\",\"stateReason\":\"Threshold Crossed: 1 datapoint (8.0) was not greater than or equal to the threshold (240.0).\",\"stateReasonData\":{\"version\":\"1.0\",\"queryDate\":\"2015-02-14T06:45:27.200+0000\",\"startDate\":\"2015-02-14T06:25:00.000+0000\",\"unit\":\"Count\",\"statistic\":\"Sum\",\"period\":300,\"recentDatapoints\":[8.0],\"threshold\":240.0}}}",
              "HistorySummary": "Alarm updated from ALARM to OK"
          },
          {
              "Timestamp": "2015-02-14T06:45:26.465Z",
              "HistoryItemType": "Action",
              "AlarmName": "ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm",
              "HistoryData": "{\"actionState\":\"Succeeded\",\"notificationResource\":\"arn:aws:sns:us-west-2:XXXXXXXXXXXX:dynamodb\",\"stateUpdateTimestamp\":\"2015-02-14T06:45:26.450+0000\",\"publishedMessage\":\"{\\\"default\\\":\\\"{\\\\\\\"AlarmName\\\\\\\":\\\\\\\"ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\\\\\\\",\\\\\\\"AlarmDescription\\\\\\\":\\\\\\\"Read Capacity Units Limit Basic Alarm for ProductCatalog\\\\\\\",\\\\\\\"AWSAccountId\\\\\\\":\\\\\\\"XXXXXXXXXXXX\\\\\\\",\\\\\\\"NewStateValue\\\\\\\":\\\\\\\"ALARM\\\\\\\",\\\\\\\"NewStateReason\\\\\\\":\\\\\\\"test alarm.\\\\\\\",\\\\\\\"StateChangeTime\\\\\\\":\\\\\\\"2015-02-14T06:45:26.450+0000\\\\\\\",\\\\\\\"Region\\\\\\\":\\\\\\\"US-West-2\\\\\\\",\\\\\\\"OldStateValue\\\\\\\":\\\\\\\"OK\\\\\\\",\\\\\\\"Trigger\\\\\\\":{\\\\\\\"MetricName\\\\\\\":\\\\\\\"ConsumedReadCapacityUnits\\\\\\\",\\\\\\\"Namespace\\\\\\\":\\\\\\\"AWS/DynamoDB\\\\\\\",\\\\\\\"Statistic\\\\\\\":\\\\\\\"SUM\\\\\\\",\\\\\\\"Unit\\\\\\\":\\\\\\\"Count\\\\\\\",\\\\\\\"Dimensions\\\\\\\":[{\\\\\\\"name\\\\\\\":\\\\\\\"TableName\\\\\\\",\\\\\\\"value\\\\\\\":\\\\\\\"ProductCatalog\\\\\\\"}],\\\\\\\"Period\\\\\\\":300,\\\\\\\"EvaluationPeriods\\\\\\\":12,\\\\\\\"ComparisonOperator\\\\\\\":\\\\\\\"GreaterThanOrEqualToThreshold\\\\\\\",\\\\\\\"Threshold\\\\\\\":240.0}}\\\",\\\"sms\\\":\\\"ALARM: \\\\\\\"ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\\\\\\\" in US-West-2\\\",\\\"email\\\":\\\"You are receiving this email because your Amazon CloudWatch Alarm \\\\\\\"ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\\\\\\\" in the US-West-2 region has entered the ALARM state, because \\\\\\\"test alarm.\\\\\\\" at \\\\\\\"Saturday 14 February, 2015 06:45:26 UTC\\\\\\\".\\\\n\\\\nView this alarm in the AWS Management Console:\\\\nhttps://console.aws.amazon.com/cloudwatch/home?region=us-west-2#s=Alarms&alarm=ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\\\\n\\\\nAlarm Details:\\\\n- Name:                       ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm\\\\n- Description:                Read Capacity Units Limit Basic Alarm for ProductCatalog\\\\n- State Change:               OK -> ALARM\\\\n- Reason for State Change:    test alarm.\\\\n- Timestamp:                  Saturday 14 February, 2015 06:45:26 UTC\\\\n- AWS Account:                XXXXXXXXXXXX\\\\n\\\\nThreshold:\\\\n- The alarm is in the ALARM state when the metric is GreaterThanOrEqualToThreshold 240.0 for 300 seconds. \\\\n\\\\nMonitored Metric:\\\\n- MetricNamespace:            AWS/DynamoDB\\\\n- MetricName:                 ConsumedReadCapacityUnits\\\\n- Dimensions:                 [TableName = ProductCatalog]\\\\n- Period:                     300 seconds\\\\n- Statistic:                  Sum\\\\n- Unit:                       Count\\\\n\\\\nState Change Actions:\\\\n- OK: \\\\n- ALARM: [arn:aws:sns:us-west-2:XXXXXXXXXXXX:dynamodb]\\\\n- INSUFFICIENT_DATA: \\\\n\\\"}\"}",
              "HistorySummary": "Successfully executed action arn:aws:sns:us-west-2:XXXXXXXXXXXX:dynamodb"
          },
          {
              "Timestamp": "2015-02-14T06:45:26.450Z",
              "HistoryItemType": "StateUpdate",
              "AlarmName": "ProductCatalog-ReadCapacityUnitsLimit-BasicAlarm",
              "HistoryData": "{\"version\":\"1.0\",\"oldState\":{\"stateValue\":\"OK\",\"stateReason\":\"Threshold Crossed: 1 datapoint (8.0) was not greater than or equal to the threshold (240.0).\",\"stateReasonData\":{\"version\":\"1.0\",\"queryDate\":\"2015-02-14T06:37:59.447+0000\",\"startDate\":\"2015-02-14T06:22:00.000+0000\",\"unit\":\"Count\",\"statistic\":\"Sum\",\"period\":300,\"recentDatapoints\":[8.0],\"threshold\":240.0}},\"newState\":{\"stateValue\":\"ALARM\",\"stateReason\":\"test alarm.\"}}",
              "HistorySummary": "Alarm updated from OK to ALARM"
          }
        ],
        "NextToken": "None___3"
      }

完了

8
6
0

Register as a new user and use Qiita more conveniently

  1. You get articles that match your needs
  2. You can efficiently read back useful information
  3. You can use dark theme
What you can do with signing up
8
6

Delete article

Deleted articles cannot be recovered.

Draft of this article would be also deleted.

Are you sure you want to delete this article?