AWS Batch container cannot access S3 via aws-cli

Question

I'm trying to run an AWS Batch job, but it is failing when calling aws-cli to copy data from s3 into the container. The error message is as follows:

fatal error: Unable to locate credentials

My job definition has an execution role with two managed policies: AmazonS3FullAccess and AmazonECSTaskExecutionRolePolicy . The container image is built from the default ubuntu:22.04 image, and has an entry point file similar to:

#!/bin/bash
set -ex

aws s3 cp ...

I've also been reading the following question: ECS Fargate task not applying role , which states that the container should have a variable AWS_CONTAINER_CREDENTIALS_RELATIVE_URI , but I don't have that. I've added a declare -x in my entry point, and this is its output when I execute the Batch job:

declare -x AWS_BATCH_CE_NAME="MyCluster"
declare -x AWS_BATCH_JOB_ATTEMPT="1"
declare -x AWS_BATCH_JOB_ID="xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
declare -x AWS_BATCH_JQ_NAME="MyQueue"
declare -x AWS_DEFAULT_REGION="us-west-2"
declare -x AWS_EXECUTION_ENV="AWS_ECS_FARGATE"
declare -x AWS_REGION="us-west-2"
declare -x DEBIAN_FRONTEND="noninteractive"
declare -x ECS_CONTAINER_METADATA_URI="http://111.111.111.1/v3/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-xxxxxxxxxx"
declare -x ECS_CONTAINER_METADATA_URI_V4="http://111.111.111.1/v4/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-xxxxxxxxxx"
declare -x HOME="/root"
declare -x HOSTNAME="ip-111-11-1-111.us-west-2.compute.internal"
declare -x OLDPWD
declare -x PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
declare -x PWD="/"
declare -x SHLVL="1"

Also, when setting up a Fargate cluster, I can see that a Task Definition has a "Task Role" in addition to the execution role. My understanding is that the "Task Role" is a role defined inside the container, while the execution role is defined to setup the container. In Batch, there is no such "Task Role". So, my question is, how can I authorize my container to access my AWS resources with aws-cli inside the container?

Answer 1

I finally figured out how to pass permissions to the container. The Job Definition has a "Job Role" which is passed directly to the ECS Task Role, but that configuration option isn't available in the AWS Console. One must register the Job Definition via API or CLI, in the --container-properties parameter:

aws batch register-job-definition --container-properties '{"jobRoleArn": "...","executionRoleArn": "..."}' ...