have created iam identity center, but how to access eb app from root user account in iamic?

Hello shwetha.

If you want your IAM identities created with IAM Identity Center just to access (read) your EB environments created by root account, you can attach a managed policy AWSElasticBeanstalkReadOnly.

The above policy contains below permissions:

{
  "Version" : "2012-10-17",
  "Statement" : [
    {
      "Sid" : "AllowAPIs",
      "Effect" : "Allow",
      "Action" : [
        "acm:ListCertificates",
        "autoscaling:DescribeAccountLimits",
        "autoscaling:DescribeAutoScalingGroups",
        "autoscaling:DescribeAutoScalingInstances",
        "autoscaling:DescribeLaunchConfigurations",
        "autoscaling:DescribePolicies",
        "autoscaling:DescribeLoadBalancers",
        "autoscaling:DescribeNotificationConfigurations",
        "autoscaling:DescribeScalingActivities",
        "autoscaling:DescribeScheduledActions",
        "cloudformation:DescribeStackResource",
        "cloudformation:DescribeStackResources",
        "cloudformation:DescribeStacks",
        "cloudformation:GetTemplate",
        "cloudformation:ListStackResources",
        "cloudformation:ListStacks",
        "cloudformation:ValidateTemplate",
        "cloudtrail:LookupEvents",
        "cloudwatch:DescribeAlarms",
        "cloudwatch:GetMetricStatistics",
        "cloudwatch:ListMetrics",
        "ec2:DescribeAccountAttributes",
        "ec2:DescribeAddresses",
        "ec2:DescribeImages",
        "ec2:DescribeInstanceAttribute",
        "ec2:DescribeInstances",
        "ec2:DescribeInstanceStatus",
        "ec2:DescribeKeyPairs",
        "ec2:DescribeLaunchTemplateVersions",
        "ec2:DescribeLaunchTemplates",
        "ec2:DescribeSecurityGroups",
        "ec2:DescribeSnapshots",
        "ec2:DescribeSpotInstanceRequests",
        "ec2:DescribeAvailabilityZones",
        "ec2:DescribeSubnets",
        "ec2:DescribeVpcs",
        "elasticbeanstalk:Check*",
        "elasticbeanstalk:Describe*",
        "elasticbeanstalk:List*",
        "elasticbeanstalk:RequestEnvironmentInfo",
        "elasticbeanstalk:RetrieveEnvironmentInfo",
        "elasticloadbalancing:DescribeInstanceHealth",
        "elasticloadbalancing:DescribeLoadBalancers",
        "elasticloadbalancing:DescribeSSLPolicies",
        "elasticloadbalancing:DescribeTargetGroups",
        "elasticloadbalancing:DescribeTargetHealth",
        "iam:GetRole",
        "iam:ListAttachedRolePolicies",
        "iam:ListInstanceProfiles",
        "iam:ListRolePolicies",
        "iam:ListRoles",
        "iam:ListServerCertificates",
        "rds:DescribeDBEngineVersions",
        "rds:DescribeDBInstances",
        "rds:DescribeOrderableDBInstanceOptions",
        "rds:DescribeDBSnapshots",
        "s3:ListAllMyBuckets",
        "sns:ListSubscriptionsByTopic",
        "sns:ListTopics",
        "sqs:ListQueues"
      ],
      "Resource" : "*"
    },
    {
      "Sid" : "AllowS3",
      "Effect" : "Allow",
      "Action" : [
        "s3:GetObject",
        "s3:GetObjectAcl",
        "s3:GetObjectVersion",
        "s3:GetObjectVersionAcl",
        "s3:GetBucketLocation",
        "s3:GetBucketPolicy",
        "s3:ListBucket"
      ],
      "Resource" : "arn:aws:s3:::elasticbeanstalk-*"
    }
  ]
}

In addition, If you want to look for more policies managed by AWS, please refer to Managing Elastic Beanstalk user policies document provided by AWS Elastic Beanstalk.

Regards,

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