Part-73: To Implement a Regional Internal Load balancer with HTTP in GCP Cloud

#googlecloud #devops #learning #cloud

Google Cloud - Regional Application Load Balancer Internal HTTP

Step-01: Introduction

Pre-requisite-1: Create Instance Templates, Create Managed Instance Groups - we already created

https://dev.to/latchudevops/part-72-to-create-a-zonal-migs-and-implement-a-regional-external-load-balancer-in-gcp-cloud-5g0b

Create Regional Application Load Balancer Internal - HTTP

Step-02: Pre-requisite-2: Reserve proxy-only subnet exclusively for regional load balancing proxies.

Goto VPC Networks -> vpc3-custom -> SUBNETS -> ADD SUBNET
Name: lb-subnet-proxyonly-us-central1
Description: lb-subnet-proxyonly-us-central1
Region: us-central1
Purpose: Regional Managed Proxy
Role: Active
IPv4 Range: 10.129.0.0/23
Click on ADD

Step-03: Pre-requisite-3: Create Firewall rule

fw-allow-proxy-only-subnet: An ingress rule that allows connections from the proxy-only subnet to reach the backends.

# Firewall Rule: Allow connections from Proxy Only Subnets for All Instances in the network
gcloud compute firewall-rules create vpc3-custom-allow-proxy-only-subnet \
    --network=vpc3-custom \
    --action=allow \
    --direction=ingress \
    --source-ranges=10.129.0.0/23 \
    --rules=tcp:80,tcp:443,tcp:8080

Step-04: Pre-requisite-4: Create Regional Health Check - HTTP

# Create Regional Health Check
gcloud compute health-checks create http regional-http-health-check --port=80 --region=us-central1

Step-05: Create Regional Application Load Balancer - HTTP

Go to Network Services -> Load Balancing -> CREATE LOAD BALANCER
Select Application Load Balancer (HTTP/S): START CONFIGURATION
Internet facing or internal only: Only between my VMs or serverless services
Global or Regional: Regional Internal Application Load Balancer
Load Balancer name: regional-lb-internal-http
Region: us-central1
Network: vpc3-custom

Backend Configuration

CLick on CREATE A BACKEND SERVICE
Name: regional-mybackend-svc1
Description: regional-mybackend-svc1
Backend type: Instance Group
Protocol: HTTP
Named Port: webserver80 (AUTO-POPULATED WHEN BACKEND IS SELECTED AS mig1-lbdemo)
Timeout: 30
BACKENDS

Instance Group: zmig-us-1
Port Numbers: 80
REST ALL LEAVE TO DEFAULTS
Click on DONE
Instance Group: zmig-us-2
Port Numbers: 80
REST ALL LEAVE TO DEFAULTS
Click on DONE

Health Check: regional-http-health-check
Security: Cloud Armor backend security policy: NONE
Click on CREATE

Routing Rules

Mode: Simple host and path rule
REST ALL LEAVE TO DEFAULTS

Frontend Configuration

Click on ADD FRONTEND IP AND PORT
Name: frontend-http
Description: frontend-http
Protocol: HTTP
Subnetwork: mysubnet1
Port: 80
IP Address: regional-internal-lb-ip1 CREATE NEW INTERNAL STATCI IP
Global access: Enable
Click on DONE

Review and Finalize

Review all settings
Click on CREATE

Step-06: Verify Load Balancer

Go to Network Services -> Load Balancing -> global-lb-external-http
Review the Tabs

LOAD BALANCERS
BACKENDS
FRONTENDS

Step-07: Test from same region: us-central1

Important Note: WAIT FOR 3 to 5 Minutes before Load Balancer is fully operational

# Connect to any VM created as part of MIG
gcloud compute ssh --zone "us-central1-c" "zmig-us-2-9jm9" --project "gcplearn9"

# Access Application
curl http://INTERNAL-LB-IP
curl http://10.135.0.8

Step-08: Test from different region: us-east1 (Global Access Enabled)

As Global Access is enabled, verify if this internal load balancer is accessible via other regions

# Create Client VM in region us-east1
gcloud compute instances create us-east1-clientvm \
    --zone=us-east1-c \
    --subnet=us-east1-subnet

# Connect to VM using gcloud
gcloud compute ssh --zone "us-east1-c" "us-east1-clientvm" 

# Access Application
curl http://INTERNAL-LB-IP
curl http://10.135.0.8

Step-09: Delete Load Balancer