Set up an HTTP load balancer with a managed instance group of 2 nginx web servers on Google Cloud Platform (Qwiklab)

http_load_balancer_setup_gcp.sh

# setup
gcloud auth list
gcloud config set compute/zone us-east1-b
gcloud config set compute/region us-east1

# create an instance template
cat << EOF > startup.sh
#! /bin/bash
apt-get update
apt-get install -y nginx
service nginx start
sed -i -- 's/nginx/Google Cloud Platform - '"\$HOSTNAME"'/' /var/www/html/index.nginx-debian.html
EOF

gcloud compute instance-templates create nginx-template \
   --metadata-from-file startup-script=startup.sh

# create a target pool
gcloud compute target-pools create nginx-pool

# create a managed instance group of 2 nginx web servers
gcloud compute instance-groups managed create nginx-group \
	--base-instance-name nginx \
	--size 2 \
	--template nginx-template \
	--target-pool nginx-pool
gcloud compute instances list

# create a firewall rule
gcloud compute firewall-rules create www-firewall --allow tcp:80

# create a forwarding rule
gcloud compute forwarding-rules create nginx-lb \
	--region us-east1 \
	--ports=80 \
	--target-pool nginx-pool
gcloud compute forwarding-rules list

# create a health check
gcloud compute http-health-checks create http-basic-check

# create a backend service and attach the managed instasnce group
gcloud compute instance-groups managed \
	set-named-ports nginx-group \
	--named-ports http:80

gcloud compute backend-services create nginx-backend \
	--protocol HTTP \
	--http-health-checks http-basic-check \
	--global

gcloud compute backend-services add-backend nginx-backend \
	--instance-group nginx-group \
	--instance-group-zone us-east1-b \
	--global

# create a url map and target the HTTP proxy
gcloud compute url-maps create web-map \
	--default-service nginx-backend

gcloud compute target-http-proxies create http-lb-proxy \
	--url-map web-map

# create a forwarding rule
gcloud compute forwarding-rules create http-content-rule \
	--global \
	--target-http-proxy http-lb-proxy \
	--ports 80
gcloud compute forwarding-rules list

2024/november. What worked for me:

REGIONS AND ZONES MUST VARY IN YOUR CASE.

2 STEP.

1. gcloud compute instance-templates create lb-backend-template
   --region=us-east1 \
   --network=default
   --subnet=default
   --tags=allow-health-check
   --machine-type=e2-medium
   --image-family=debian-11
   --image-project=debian-cloud
   --metadata-from-file=startup-script=startup.sh

2. gcloud compute target-pools create nginx-pool --region=us-east1

3. gcloud compute instance-groups managed create lb-backend-group --base-instance-name nginx --template=lb-backend-template --size=2 --target-pool nginx-pool --zone=us-east1-c

4. gcloud compute firewall-rules create www-firewall --allow tcp:80

change the rule as necessary in your case
5. gcloud compute firewall-rules create permit-tcp-rule-649 --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

6. gcloud compute addresses create lb-ipv4-1 --ip-version=IPV4 --global

7. gcloud compute health-checks create http http-basic-check --port 80

8. gcloud compute forwarding-rules create nginx-lb --region us-east1 --ports=80 --target-pool nginx-pool

9. gcloud compute http-health-checks create http-basic-check

10. gcloud compute instance-groups managed set-named-ports lb-backend-group
    --named-ports http:80
    --zone=us-east1-c

11. gcloud compute backend-services create web-backend-service --protocol=HTTP --port-name=http --health-checks=http-basic-check --global

12. gcloud compute backend-services add-backend web-backend-service --instance-group=lb-backend-group --instance-group-zone=us-east1-c --global

13. gcloud compute url-maps create web-map-http --default-service web-backend-service

14. gcloud compute target-http-proxies create http-lb-proxy --url-map web-map-http

15. gcloud compute forwarding-rules create http-content-rule --address=lb-ipv4-1 --global --target-http-proxy=http-lb-proxy --ports=80