To storage your AWS ELB access log to ASW S3. We use Terraform template below the below:

1. Create a new S3 bucket called “elb-log.davidwzhang.com”
2. Define a bucket policy which grant Elastic Load Balancing access to the newly created S3 bucket “elb-log.davidwzhang.com”. As you know,  each AWS region has its own account ID for Elastic Load Balancing. These account IDs can be found in the link: http://docs.aws.amazon.com/elasticloadbalancing/latest/classic/enable-access-logs.html#d0e10520. variable “aws_elb_account_id. As my template for ap-southeast-2 region,  the account ID for  is 783225319266

Terraform Template:

provider “aws” {
region = “ap-southeast-2”
shared_credentials_file = “${pathexpand(“~/.aws/credentials”)}”
#shared_credentials_file = “/home/dzhang/.aws/credentials”
}

resource “aws_s3_bucket” “elb” {
bucket = “elb-log.davidwzhang.com”
policy = <<EOF
{
“Version”: “2012-10-17”,
“Statement”: [
{
“Effect”: “Allow”,
“Principal”: {
“AWS”: “arn:aws:iam::783225319266:root”
},
“Action”: “s3:PutObject”,
“Resource”: “arn:aws:s3:::elb-log.davidwzhang.com/*”
}
]
}
EOF
}

output “s3_bukcet_arn” {
value = “${aws_s3_bucket.elb.arn}”
}

To enable the access logging for ELB.  we need to update our ELB resource as the below:

resource “aws_elb” “elb1” {
name = “terraform-elb”
availability_zones = [“${data.aws_availability_zones.allzones.names}”]
security_groups = [“${aws_security_group.elbsg.id}”]
access_logs {
bucket = “elb-log.davidwzhang.com”
bucket_prefix = “elb”
interval = 5
}
listener {
instance_port = 80
instance_protocol = “http”
lb_port = 80
lb_protocol = “http”
}

health_check {
healthy_threshold = 2
unhealthy_threshold = 2
timeout = 3
target = “HTTP:80/”
interval = 30
}

instances = [“${aws_instance.web1.id}”,”${aws_instance.web2.id}”]
cross_zone_load_balancing = true
idle_timeout = 400
connection_draining = true
connection_draining_timeout = 400

tags {
Name = “terraform-elb”
}
}

Please note I changed access_logs interval to 5mins in the ELB resource defination so that we can verify the output of ELB access log quickly. In production environment, you possibly want change this interval longer, e.g. 120mins.

Output:

• ELB configuration of access_log in AWS Console

• S3 bucket for ELB access log

• S3 bucket prefix

• AWS Region

• ELB access-log file in AWS console

• ELB access-log content