If you have an AWS ACM (Amazon Certificate Manager) certificate that is going to expire in less than 45 days, you will need to renew it in order to avoid any service disruptions. Here are the step-by-step instructions on how to remediate this issue using AWS CLI:

1. Open your terminal or command prompt and make sure you have the AWS CLI installed and configured with your AWS account credentials.

2. Run the following command to list all your certificates:

aws acm list-certificates

3. Identify the certificate that needs to be renewed and note down its ARN (Amazon Resource Name).

4. Run the following command to check the status of the certificate:

aws acm describe-certificate --certificate-arn <certificate-arn>

5. Check the “NotAfter” field in the output of the above command to see the expiration date of the certificate.

6. If the certificate is going to expire in less than 45 days, run the following command to renew it:

aws acm renew-certificate --certificate-arn <certificate-arn>

7. Once the renewal request is submitted, you will receive a confirmation email from AWS. Follow the instructions in the email to complete the renewal process.

8. After the certificate is renewed, you will need to update it in your application or web server to avoid any service disruptions.

That’s it! By following these steps, you will be able to remediate the issue of AWS ACM certificates renewal under 45 days using AWS CLI.

1. First, you need to install the AWS SDK for Python (Boto3) and configure your AWS credentials on your local machine.

2. Next, you need to write a Python script that will use the Boto3 library to check the expiration date of all ACM certificates in your AWS account.

3. You can use the boto3.client('acm').list_certificates() method to list all the certificates in your account.

4. Then, you can loop through each certificate and check if its expiration date is less than 45 days from the current date using the datetime module.

5. If a certificate is about to expire, you can use the boto3.client('acm').renew_certificate() method to renew it.

6. Finally, you can schedule the script to run periodically using a tool like AWS Lambda or cron.

Here is a sample Python code to get you started:

import boto3
from datetime import datetime, timedelta

# Set the AWS region and create an ACM client
region = 'us-east-1'
acm = boto3.client('acm', region_name=region)

# Get the list of all certificates in the account
certificates = acm.list_certificates()['CertificateSummaryList']

# Loop through each certificate and check if it needs to be renewed
for cert in certificates:
    cert_arn = cert['CertificateArn']
    cert_info = acm.describe_certificate(CertificateArn=cert_arn)['Certificate']
    expiration_date = cert_info['NotAfter']
    days_left = (expiration_date - datetime.now()).days

    if days_left < 45:
        # Renew the certificate
        acm.renew_certificate(CertificateArn=cert_arn)
        print(f'Renewed certificate {cert_arn}')

Note: Make sure to test the script in a non-production environment before running it on your production AWS account.