March || Level 1 || 3 Set Up Network and HTTP Load Balancers

 export REGION=

export ZONE=

gcloud config set compute/region $REGION

gcloud config set compute/zone $ZONE

  gcloud compute instances create www1 \

    --zone=$ZONE \

    --tags=network-lb-tag \

    --machine-type=e2-small \

    --image-family=debian-11 \

    --image-project=debian-cloud \

    --metadata=startup-script='#!/bin/bash

      apt-get update

      apt-get install apache2 -y

      service apache2 restart

      echo "

<h3>Web Server: www1</h3>" | tee /var/www/html/index.html'

  gcloud compute instances create www2 \

    --zone=$ZONE \

    --tags=network-lb-tag \

    --machine-type=e2-small \

    --image-family=debian-11 \

    --image-project=debian-cloud \

    --metadata=startup-script='#!/bin/bash

      apt-get update

      apt-get install apache2 -y

      service apache2 restart

      echo "

<h3>Web Server: www2</h3>" | tee /var/www/html/index.html'

  gcloud compute instances create www3 \

    --zone=$ZONE  \

    --tags=network-lb-tag \

    --machine-type=e2-small \

    --image-family=debian-11 \

    --image-project=debian-cloud \

    --metadata=startup-script='#!/bin/bash

      apt-get update

      apt-get install apache2 -y

      service apache2 restart

      echo "

<h3>Web Server: www3</h3>" | tee /var/www/html/index.html'

gcloud compute firewall-rules create www-firewall-network-lb \

    --target-tags network-lb-tag --allow tcp:80

gcloud compute instances list

gcloud compute addresses create network-lb-ip-1 \

  --region $REGION

gcloud compute http-health-checks create basic-check

gcloud compute target-pools create www-pool \

  --region $REGION --http-health-check basic-check

gcloud compute target-pools add-instances www-pool \

    --instances www1,www2,www3

gcloud compute forwarding-rules create www-rule \

    --region  $REGION \

    --ports 80 \

    --address network-lb-ip-1 \

    --target-pool www-pool

gcloud compute forwarding-rules describe www-rule --region $REGION

IPADDRESS=$(gcloud compute forwarding-rules describe www-rule --region $REGION --format="json" | jq -r .IPAddress)

echo $IPADDRESS

while true; do curl -m1 $IPADDRESS; done

gcloud compute instance-templates create lb-backend-template \

   --region=$REGION \

   --network=default \

   --subnet=default \

   --tags=allow-health-check \

   --machine-type=e2-medium \

   --image-family=debian-11 \

   --image-project=debian-cloud \

   --metadata=startup-script='#!/bin/bash

     apt-get update

     apt-get install apache2 -y

     a2ensite default-ssl

     a2enmod ssl

     vm_hostname="$(curl -H "Metadata-Flavor:Google" \

     http://169.254.169.254/computeMetadata/v1/instance/name)"

     echo "Page served from: $vm_hostname" | \

     tee /var/www/html/index.html

     systemctl restart apache2'

gcloud compute instance-groups managed create lb-backend-group \

   --template=lb-backend-template --size=2 --zone=$ZONE

gcloud compute firewall-rules create fw-allow-health-check \

  --network=default \

  --action=allow \

  --direction=ingress \

  --source-ranges=130.211.0.0/22,35.191.0.0/16 \

  --target-tags=allow-health-check \

  --rules=tcp:80

gcloud compute addresses create lb-ipv4-1 \

  --ip-version=IPV4 \

  --global

gcloud compute addresses describe lb-ipv4-1 \

  --format="get(address)" \

  --global

gcloud compute health-checks create http http-basic-check \

  --port 80

gcloud compute backend-services create web-backend-service \

  --protocol=HTTP \

  --port-name=http \

  --health-checks=http-basic-check \

  --global

gcloud compute backend-services add-backend web-backend-service \

  --instance-group=lb-backend-group \

  --instance-group-zone=$ZONE \

  --global

gcloud compute url-maps create web-map-http \

    --default-service web-backend-service

gcloud compute target-http-proxies create http-lb-proxy \

    --url-map web-map-http

gcloud compute forwarding-rules create http-content-rule \

   --address=lb-ipv4-1\

   --global \

   --target-http-proxy=http-lb-proxy \

   --ports=80