# Tutorial: Add a CloudWatch Logs IAM policy
<a name="cwl_iam_policy"></a>

Before your jobs can send log data and detailed metrics to CloudWatch Logs, you must create an IAM policy that uses the CloudWatch Logs APIs. After you create the IAM policy, attach it to the `ecsInstanceRole` role.

**Note**  
If the `ECS-CloudWatchLogs` policy isn't attached to the `ecsInstanceRole` role, basic metrics can still be sent to CloudWatch Logs. However, the basic metrics don't include log data or detailed metrics such as free disk space.

Amazon Batch compute environments use Amazon EC2 resources. When you create a compute environment using the Amazon Batch first-run wizard, Amazon Batch creates the `ecsInstanceRole` role and configures the environment with it.

If you aren't using the first-run wizard, you can specify the `ecsInstanceRole` role when you create a compute environment in the Amazon Command Line Interface or Amazon Batch API. For more information, see the [Amazon CLI Command Reference](https://docs.amazonaws.cn/cli/latest/reference/) or [Amazon Batch API Reference](https://docs.amazonaws.cn/batch/latest/APIReference/API_CreateComputeEnvironment.html).

**To create the `ECS-CloudWatchLogs` IAM policy**

1. Open the IAM console at [https://console.amazonaws.cn/iam/](https://console.amazonaws.cn/iam/).

1. In the navigation pane, choose **Policies**. 

1. Choose **Create policy**.

1. Choose **JSON**, then enter the following policy:

------
#### [ JSON ]

****  

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

------

1. Choose **Next: Tags**.

1. (Optional) For **Add tags**, choose **Add tag** to add a tag to the policy.

1. Choose **Next: Review**.

1. On the **Review policy** page, for **Name**, enter **ECS-CloudWatchLogs**, and then enter an optional **Description**.

1. Choose **Create policy**.

**To attach the `ECS-CloudWatchLogs` policy to `ecsInstanceRole`**

1. Open the IAM console at [https://console.amazonaws.cn/iam/](https://console.amazonaws.cn/iam/).

1. In the navigation pane, choose **Roles**. 

1. Choose `ecsInstanceRole`. If the role doesn't exist, follow the procedures in [Amazon ECS instance role](instance_IAM_role.md) to create the role.

1. Choose **Add Permissions**, then choose **Attach policies**.

1. Choose the **ECS-CloudWatchLogs** policy and then choose **Attach policy**.