Using identity-based policies (IAM policies) for CloudWatch Logs

This topic provides examples of identity-based policies in which an account administrator can attach permissions policies to IAM identities (that is, users, groups, and roles).

Important

We recommend that you first review the introductory topics that explain the basic concepts and options available for you to manage access to your CloudWatch Logs resources. For more information, see Overview of managing access permissions to your CloudWatch Logs resources.

This topic covers the following:

• Permissions required to use the CloudWatch console

• AWS managed (predefined) policies for CloudWatch Logs

• Customer managed policy examples

The following is an example of a permissions policy:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "logs:CreateLogGroup",
        "logs:CreateLogStream",
        "logs:PutLogEvents",
        "logs:DescribeLogStreams"
    ],
      "Resource": [
        "arn:aws:logs:*:*:*"
    ]
  }
 ]
}

This policy has one statement that grants permissions to create log groups and log streams, to upload log events to log streams, and to list details about log streams.

The wildcard character (*) at the end of the Resource value means that the statement allows permission for the logs:CreateLogGroup, logs:CreateLogStream, logs:PutLogEvents, and logs:DescribeLogStreams actions on any log group. To limit this permission to a specific log group, replace the wildcard character (*) in the resource ARN with the specific log group ARN. For more information about the sections within an IAM policy statement, see IAM Policy Elements Reference in IAM User Guide. For a list showing all of the CloudWatch Logs actions, see CloudWatch Logs permissions reference.

Permissions required to use the CloudWatch console

For a user to work with CloudWatch Logs in the CloudWatch console, that user must have a minimum set of permissions that allows the user to describe other AWS resources in their AWS account. In order to use CloudWatch Logs in the CloudWatch console, you must have permissions from the following services:

• CloudWatch

• CloudWatch Logs

• OpenSearch Service

• IAM

• Kinesis

• Lambda

• Amazon S3

If you create an IAM policy that is more restrictive than the minimum required permissions, the console won't function as intended for users with that IAM policy. To ensure that those users can still use the CloudWatch console, also attach the CloudWatchReadOnlyAccess managed policy to the user, as described in AWS managed (predefined) policies for CloudWatch Logs.

You don't need to allow minimum console permissions for users that are making calls only to the AWS CLI or the CloudWatch Logs API.

The full set of permissions required to work with the CloudWatch console for a user who is not using the console to manage log subscriptions are:

• cloudwatch:getMetricData

• cloudwatch:listMetrics

• logs:cancelExportTask

• logs:createExportTask

• logs:createLogGroup

• logs:createLogStream

• logs:deleteLogGroup

• logs:deleteLogStream

• logs:deleteMetricFilter

• logs:deleteQueryDefinition

• logs:deleteRetentionPolicy

• logs:deleteSubscriptionFilter

• logs:describeExportTasks

• logs:describeLogGroups

• logs:describeLogStreams

• logs:describeMetricFilters

• logs:describeQueryDefinitions

• logs:describeSubscriptionFilters

• logs:filterLogEvents

• logs:getLogEvents

• logs:putMetricFilter

• logs:putQueryDefinition

• logs:putRetentionPolicy

• logs:putSubscriptionFilter

• logs:testMetricFilter

For a user who will also be using the console to manage log subscriptions, the following permissions are also required:

• es:describeElasticsearchDomain

• es:listDomainNames

• iam:attachRolePolicy

• iam:createRole

• iam:getPolicy

• iam:getPolicyVersion

• iam:getRole

• iam:listAttachedRolePolicies

• iam:listRoles

• kinesis:describeStreams

• kinesis:listStreams

• lambda:addPermission

• lambda:createFunction

• lambda:getFunctionConfiguration

• lambda:listAliases

• lambda:listFunctions

• lambda:listVersionsByFunction

• lambda:removePermission

• s3:listBuckets

AWS managed (predefined) policies for CloudWatch Logs

AWS addresses many common use cases by providing standalone IAM policies that are created and administered by AWS. Managed policies grant necessary permissions for common use cases so you can avoid having to investigate what permissions are needed. For more information, see AWS Managed Policies in the IAM User Guide.

The following AWS managed policies, which you can attach to users and roles in your account, are specific to CloudWatch Logs:

• CloudWatchLogsFullAccess – Grants full access to CloudWatch Logs.

• CloudWatchLogsReadOnlyAccess – Grants read-only access to CloudWatch Logs.

CloudWatchLogsFullAccess

The CloudWatchLogsFullAccess policy grants full access to CloudWatch Logs. The contents are as follows:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "logs:*"
            ],
            "Effect": "Allow",
            "Resource": "*"
        }
    ]
}

CloudWatchLogsReadOnlyAccess

The CloudWatchLogsReadOnlyAccess policy grants read-only access to CloudWatch Logs. The contents are as follows:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "logs:Describe*",
                "logs:Get*",
                "logs:List*",
                "logs:StartQuery",
                "logs:StopQuery",
                "logs:TestMetricFilter",
                "logs:FilterLogEvents"
            ],
            "Resource": "*"
        }
    ]
}

Customer managed policy examples

You can create your own custom IAM policies to allow permissions for CloudWatch Logs actions and resources. You can attach these custom policies to the IAM users or groups that require those permissions.

In this section, you can find example user policies that grant permissions for various CloudWatch Logs actions. These policies work when you are using the CloudWatch Logs API, AWS SDKs, or the AWS CLI.

Example 1: Allow full access to CloudWatch Logs

The following policy allows a user to access all CloudWatch Logs actions.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Action": [
        "logs:*"
      ],
      "Effect": "Allow",
      "Resource": "*"
    }
  ]
}

Example 2: Allow read-only access to CloudWatch Logs

AWS provides a CloudWatchLogsReadOnlyAccess policy that enables read-only access to CloudWatch Logs data. This policy includes the following permissions.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": [
                "logs:Describe*",
                "logs:Get*",
                "logs:List*",
                "logs:StartQuery",
                "logs:StopQuery",
                "logs:TestMetricFilter",
                "logs:FilterLogEvents"
            ],
            "Effect": "Allow",
            "Resource": "*"
        }
    ]
}

Example 3: Allow access to one log group

The following policy allows a user to read and write log events in one specified log group.

Important

The :* at the end of the log group name in the Resource line is required to indicate that the policy applies to all log streams in this log group. If you omit :*, the policy will not be enforced.

{
   "Version":"2012-10-17",
   "Statement":[
      {
      "Action": [
        "logs:CreateLogStream",
        "logs:DescribeLogStreams",
        "logs:PutLogEvents",
        "logs:GetLogEvents"
      ],
      "Effect": "Allow",
      "Resource": "arn:aws:logs:us-west-2:123456789012:log-group:SampleLogGroupName:*"
      }
   ]
}

Use tagging and IAM policies for control at the log group level

You can grant users access to certain log groups while preventing them from accessing other log groups. To do so, tag your log groups and use IAM policies that refer to those tags. To apply tags to a log group, you need to have either the logs:TagResource or logs:TagLogGroup permission. This applies both if you are assigning tags to the log group when you create it. or assigning them later.

For more information about tagging log groups, see Tag log groups in Amazon CloudWatch Logs.

When you tag log groups, you can then grant an IAM policy to a user to allow access to only the log groups with a particular tag. For example, the following policy statement grants access to only log groups with the value of Green for the tag key Team.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": [
                "logs:*"
            ],
            "Effect": "Allow",
            "Resource": "*",
            "Condition": {
                "StringLike": {
                    "aws:ResourceTag/Team": "Green"
                }
            }
        }
    ]
}

For more information about using IAM policy statements, see Controlling Access Using Policies in the IAM User Guide.