Before setting up CodeCommit for SSH users, we need the AWS CLI installed and configured with the respective AWS account. To install the AWS CLI on our development machine, we need to perform these steps:

1. We need to install python-pip and AWS CLI tools. Usually, in CentOS/RHEL, python-pip comes with EPEL (Extra Package for Enterprise Linux):

    # yum install epel-release python-pip
    # pip install awscli

2. Once we have the awscli command installed in our system, we have to configure it using the access and secret Key, as well as the region we will use the AWS account in. If you remember, we had created a user while generating the https git credentials, but at that moment, we also downloaded another type of credentials, the secret and access key. So, we need that over here.
3. Now, let's configure AWS CLI:

    awsstar@awsstar:~$ aws configure
     AWS Access Key ID [None]: AKIxxxxxxxxxxxxxDDA
     AWS Secret Access Key [None]: b+GEuc2u3xxxxxxxxxxxxxx+av/5eK
     Default region name [None]: us-east-1
     Default output format [None]:

4. Once the configuration is done, let's try to list the repository:

    awsstar@awsstar:~$ aws codecommit list-repositories
     {
     "repositories": [
     {
     "repositoryName": "NixSrj",
     "repositoryId": "73caf1e3-65a9-44bf-8c6a-a3bd3e0260b0"
     },
     {
     "repositoryName": "ECS-POC",
     "repositoryId": "62063220-b0fc-4519-9d54-896be46a7521"
     },
     {
     "repositoryName": "terraform-Openshift",
     "repositoryId": "20f88492-81bb-4068-8867-5d17a1d3ec5b"
     }
     ]
     }

5. So it's showing the repository, which means the credentials are working fine and we are good to go to create a repository now.