title: AWS RDS backup to S3 fails
body: <p>We have an option group attached to one of our SQL Server instances to backup to an S3 bucket. When we attempt to run a backup using the <code>rds_backup_database</code> stored procedure, we get the following errors:</p>
  <pre><code>[2021-03-18 20:20:22.260] Aborted the task because of a task failure or an overlap with your preferred backup window for RDS automated backup.
  [2021-03-18 20:20:22.270] Task has been aborted
  [2021-03-18 20:20:22.270] Access Denied
  </code></pre>
  <p>Everything I've read says that this means the IAM role used for the backup and restore option group doesn't have the proper permissions to the S3 bucket.</p>
  <p>Yet, everything appears to be configured correctly. Here is the permissions configuration for that role.</p>
  <pre><code>{
      &quot;Version&quot;: &quot;2012-10-17&quot;,
      &quot;Statement&quot;: [
          {
              &quot;Effect&quot;: &quot;Allow&quot;,
              &quot;Action&quot;: [
                  &quot;s3:ListBucket&quot;,
                  &quot;s3:GetBucketLocation&quot;
              ],
              &quot;Resource&quot;: [
                  &quot;arn:aws:s3:::sabmssqldevbackups&quot;
              ]
          },
          {
              &quot;Effect&quot;: &quot;Allow&quot;,
              &quot;Action&quot;: [
                  &quot;s3:GetObjectMetaData&quot;,
                  &quot;s3:GetObject&quot;,
                  &quot;s3:PutObject&quot;,
                  &quot;s3:ListMultipartUploadParts&quot;,
                  &quot;s3:AbortMultipartUpload&quot;
              ],
              &quot;Resource&quot;: [
                  &quot;arn:aws:s3:::sabmssqldevbackups/sabmssqldev/*&quot;
              ]
          }
      ]
  }
  </code></pre>
  <p>As for the backup window, it's configured for a half hour just after midnight, so we can't be conflicting with that.</p>
  <p>Another peculiarity is that our RDS instance resides in the region <code>us-east-2a</code>. I can't find any information on what <code>us-east-2a</code> is. You can't select it when you have the option to select regions. Our S3 bucket is in <code>us-east-2</code>, as it should be. Are the two regions the same, or is this mismatch the cause of our failure to perform backups?</p>