# Set Up Network and Application Load Balancers - GSP007
## **Overview**
In this hands-on lab you learn the differences between a Network Load Balancer and an Application Load Balancer, and how to set them up for your applications running on Compute Engine virtual machines (VMs).
There are several ways you can [load balance on Google Cloud](https://cloud.google.com/load-balancing/docs/load-balancing-overview#a_closer_look_at_cloud_load_balancers). This lab takes you through the setup of the following load balancers:
* [Network Load Balancer](https://cloud.google.com/compute/docs/load-balancing/network/)
* [Application Load Balancer](https://cloud.google.com/compute/docs/load-balancing/http/)
You are encouraged to type the commands yourself, which can help you learn the core concepts. Many labs include a code block that contains the required commands. You can easily copy and paste the commands from the code block into the appropriate places during the lab.
### Objectives
In this lab, you learn how to perform the following tasks:
* Configure the default region and zone for your resources.
* Create multiple web server instances.
* Configure a load balancing service.
* Create an Application Load Balancer.
## **Setup and requirements**
### Before you click the Start Lab button
Read these instructions. Labs are timed and you cannot pause them. The timer, which starts when you click **Start Lab**, shows how long Google Cloud resources are made available to you.
This hands-on lab lets you do the lab activities in a real cloud environment, not in a simulation or demo environment. It does so by giving you new, temporary credentials you use to sign in and access Google Cloud for the duration of the lab.
To complete this lab, you need:
* Access to a standard internet browser (Chrome browser recommended).
**Note:** Use an Incognito (recommended) or private browser window to run this lab. This prevents conflicts between your personal account and the student account, which may cause extra charges incurred to your personal account.
* Time to complete the lab—remember, once you start, you cannot pause a lab.
**Note:** Use only the student account for this lab. If you use a different Google Cloud account, you may incur charges to that account.
### How to start your lab and sign in to the Google Cloud console
1. Click the **Start Lab** button. If you need to pay for the lab, a dialog opens for you to select your payment method. On the left is the Lab Details pane with the following:
* The Open Google Cloud console button
* Time remaining
* The temporary credentials that you must use for this lab
* Other information, if needed, to step through this lab
2. Click **Open Google Cloud console** (or right-click and select **Open Link in Incognito Window** if you are running the Chrome browser).
The lab spins up resources, and then opens another tab that shows the Sign in page.
***Tip:*** Arrange the tabs in separate windows, side-by-side.
**Note:** If you see the **Choose an account** dialog, click **Use Another Account**.
3. If necessary, copy the **Username** below and paste it into the **Sign in** dialog.
```apache
student-02-a5fc870c72ae@qwiklabs.net
```
You can also find the Username in the Lab Details pane.
4. Click **Next**.
5. Copy the **Password** below and paste it into the **Welcome** dialog.
```apache
sy4q8PAx9pj2
```
You can also find the Password in the Lab Details pane.
6. Click **Next**.
**Important:** You must use the credentials the lab provides you. Do not use your Google Cloud account credentials.
**Note:** Using your own Google Cloud account for this lab may incur extra charges.
7. Click through the subsequent pages:
* Accept the terms and conditions.
* Do not add recovery options or two-factor authentication (because this is a temporary account).
* Do not sign up for free trials.
After a few moments, the Google Cloud console opens in this tab.
**Note:** To access Google Cloud products and services, click the **Navigation menu** or type the service or product name in the **Search** field.
![Navigation menu icon and Search field](https://cdn.qwiklabs.com/9Fk8NYFp3quE9mF%2FilWF6%2FlXY9OUBi3UWtb2Ne4uXNU%3D align="left")
### Activate Cloud Shell
Cloud Shell is a virtual machine that is loaded with development tools. It offers a persistent 5GB home directory and runs on the Google Cloud. Cloud Shell provides command-line access to your Google Cloud resources.
1. Click **Activate Cloud Shell** at the top of the Google Cloud console.
2. Click through the following windows:
* Continue through the Cloud Shell information window.
* Authorize Cloud Shell to use your credentials to make Google Cloud API calls.
When you are connected, you are already authenticated, and the project is set to your **Project\_ID**, `qwiklabs-gcp-03-de313196ef42`. The output contains a line that declares the **Project\_ID** for this session:
```apache
Your Cloud Platform project in this session is set to qwiklabs-gcp-03-de313196ef42
```
`gcloud` is the command-line tool for Google Cloud. It comes pre-installed on Cloud Shell and supports tab-completion.
3. (Optional) You can list the active account name with this command:
```apache
gcloud auth list
```
4. Click **Authorize**.
**Output:**
```apache
ACTIVE: *
ACCOUNT: student-02-a5fc870c72ae@qwiklabs.net
To set the active account, run:
$ gcloud config set account `ACCOUNT`
```
5. (Optional) You can list the project ID with this command:
```apache
gcloud config list project
```
**Output:**
```apache
[core]
project = qwiklabs-gcp-03-de313196ef42
```
**Note:** For full documentation of `gcloud`, in Google Cloud, refer to [the gcloud CLI overview guide](https://cloud.google.com/sdk/gcloud).
## **Task 1. Set the default region and zone for all resources**
1. Set the default region:
```apache
gcloud config set compute/region us-east1
```
2. In Cloud Shell, set the default zone:
```apache
gcloud config set compute/zone us-east1-d
```
Learn more about choosing zones and regions in Compute Engine's [Regions and zones](https://cloud.google.com/compute/docs/zones) documentation.
## **Task 2. Create multiple web server instances**
For this load balancing scenario, you create three Compute Engine VM instances and install Apache on them, then add a firewall rule that allows HTTP traffic to reach the instances.
The code provided sets the zone to `us-east1-d`. Setting the `tags` field lets you reference these instances all at once, such as with a firewall rule. These commands also install Apache on each instance and give each instance a unique home page.
1. Create a virtual machine, `www1`, in your default zone using the following code:
```apache
gcloud compute instances create www1 \
--zone=us-east1-d \
--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 "
Web Server: www1
" | tee /var/www/html/index.html'
```
2. Create a virtual machine, `www2`, in your default zone using the following code:
```apache
gcloud compute instances create www2 \
--zone=us-east1-d \
--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 "
Web Server: www2
" | tee /var/www/html/index.html'
```
3. Create a virtual machine, `www3`, in your default zone.
```apache
gcloud compute instances create www3 \
--zone=us-east1-d \
--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 "
Web Server: www3
" | tee /var/www/html/index.html'
```
4. Create a firewall rule to allow external traffic to the VM instances:
```apache
gcloud compute firewall-rules create www-firewall-network-lb \
--target-tags network-lb-tag --allow tcp:80
```
Now you need to get the external IP addresses of your instances and verify that they are running.
5. Run the following to list your instances. You'll see their IP addresses in the `EXTERNAL_IP` column:
```apache
gcloud compute instances list
```
6. Verify that each instance is running with `curl`, replacing **\[IP\_ADDRESS\]** with the external IP address for each of your VMs:
```apache
curl http://[IP_ADDRESS]
```
Click **Check my progress** to verify that you've created a group of web servers.
Create multiple web server instances
Check my progress
## **Task 3. Configure the load balancing service**
When you configure the load balancing service, your virtual machine instances receives packets that are destined for the static external IP address you configure. Instances made with a Compute Engine image are automatically configured to handle this IP address.
**Note:** Learn more about how to set up Network Load Balancing from the [Backend service-based external passthrough Network Load Balancer overview](https://cloud.google.com/compute/docs/load-balancing/network/) guide.
1. Create a static external IP address for your load balancer:
```apache
gcloud compute addresses create network-lb-ip-1 \
--region us-east1
```
**Output:**
```apache
Created [https://www.googleapis.com/compute/v1/projects/qwiklabs-gcp-03-xxxxxxxxxxx/regions/us-east1/addresses/network-lb-ip-1].
```
2. Add a legacy HTTP health check resource:
```apache
gcloud compute http-health-checks create basic-check
```
3. Add a target pool in the same region as your instances. Run the following to create the target pool and use the health check, which is required for the service to function:
```apache
gcloud compute target-pools create www-pool \
--region us-east1 --http-health-check basic-check
```
4. Add the instances to the pool:
```apache
gcloud compute target-pools add-instances www-pool \
--instances www1,www2,www3
```
5. Add a forwarding rule:
```apache
gcloud compute forwarding-rules create www-rule \
--region us-east1 \
--ports 80 \
--address network-lb-ip-1 \
--target-pool www-pool
```
Click **Check my progress** to verify that you've created an L4 Network Load Balancer that points to the web servers.
Configure the load balancing service
Check my progress
## **Task 4. Send traffic to your instances**
Now that the load balancing service is configured, you can start sending traffic to the forwarding rule and watch the traffic be dispersed to different instances.
1. Enter the following command to view the external IP address of the www-rule forwarding rule used by the load balancer:
```apache
gcloud compute forwarding-rules describe www-rule --region us-east1
```
2. Access the external IP address:
```apache
IPADDRESS=$(gcloud compute forwarding-rules describe www-rule --region us-east1 --format="json" | jq -r .IPAddress)
```
3. Show the external IP address:
```apache
echo $IPADDRESS
```
4. Use the `curl` command to access the external IP address, replacing `IP_ADDRESS` with an external IP address from the previous command:
```apache
while true; do curl -m1 $IPADDRESS; done
```
The response from the `curl` command alternates randomly among the three instances. If your response is initially unsuccessful, wait approximately 30 seconds for the configuration to be fully loaded and for your instances to be marked healthy before trying again.
5. Use **Ctrl** + **C** to stop running the command.
## **Task 5. Create an Application Load Balancer**
Application Load Balancing is implemented on Google Front End (GFE). GFEs are distributed globally and operate together using Google's global network and control plane. You can configure URL rules to route some URLs to one set of instances and route other URLs to other instances.
Requests are always routed to the instance group that is closest to the user, if that group has enough capacity and is appropriate for the request. If the closest group does not have enough capacity, the request is sent to the closest group that **does** have capacity.
To set up a load balancer with a Compute Engine backend, your VMs need to be in an instance group. The managed instance group provides VMs running the backend servers of an external Application Load Balancer. For this lab, backends serve their own hostnames.
1. First, create the load balancer template:
```apache
gcloud compute instance-templates create lb-backend-template \
--region=us-east1 \
--network=default \
--subnet=default \
--tags=allow-health-check \
--machine-type=e2-medium \
--image-family=debian-11 \
--image-project=debian-cloud \
--metadata=startup-script='#!/bin/bash
apt-get update
apt-get install apache2 -y
a2ensite default-ssl
a2enmod ssl
vm_hostname="$(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'
```
[Managed instance groups](https://cloud.google.com/compute/docs/instance-groups) (MIGs) let you operate apps on multiple identical VMs. You can make your workloads scalable and highly available by taking advantage of automated MIG services, including: autoscaling, autohealing, regional (multiple zone) deployment, and automatic updating.
2. Create a managed instance group based on the template:
```apache
gcloud compute instance-groups managed create lb-backend-group \
--template=lb-backend-template --size=2 --zone=us-east1-d
```
3. Create the `fw-allow-health-check` firewall rule.
```apache
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
```
**Note:** The ingress rule allows traffic from the Google Cloud health checking systems (`130.211.0.0/22` and `35.191.0.0/16`). This lab uses the target tag `allow-health-check` to identify the VMs
4. Now that the instances are up and running, set up a global static external IP address that your customers use to reach your load balancer:
```apache
gcloud compute addresses create lb-ipv4-1 \
--ip-version=IPV4 \
--global
```
**Note the IPv4 address that was reserved:**
```apache
gcloud compute addresses describe lb-ipv4-1 \
--format="get(address)" \
--global
```
Click here for hint!
5. Create a health check for the load balancer:
```apache
gcloud compute health-checks create http http-basic-check \
--port 80
```
**Note:** Google Cloud provides health checking mechanisms that determine whether backend instances respond properly to traffic. For more information, please refer to the [Creating health checks](https://cloud.google.com/load-balancing/docs/health-checks) documentation.
6. Create a backend service:
```apache
gcloud compute backend-services create web-backend-service \
--protocol=HTTP \
--port-name=http \
--health-checks=http-basic-check \
--global
```
7. Add your instance group as the backend to the backend service:
```apache
gcloud compute backend-services add-backend web-backend-service \
--instance-group=lb-backend-group \
--instance-group-zone=us-east1-d \
--global
```
8. Create a [URL map](https://cloud.google.com/load-balancing/docs/url-map-concepts) to route the incoming requests to the default backend service:
```apache
gcloud compute url-maps create web-map-http \
--default-service web-backend-service
```
**Note:** URL map is a Google Cloud configuration resource used to route requests to backend services or backend buckets. For example, with an external Application Load Balancer, you can use a single URL map to route requests to different destinations based on the rules configured in the URL map:
* Requests for https://example.com/video go to one backend service.
* Requests for https://example.com/audio go to a different backend service.
* Requests for https://example.com/images go to a Cloud Storage backend bucket.
* Requests for any other host and path combination go to a default backend service.
9. Create a target HTTP proxy to route requests to your URL map:
```apache
gcloud compute target-http-proxies create http-lb-proxy \
--url-map web-map-http
```
10. Create a global forwarding rule to route incoming requests to the proxy:
```apache
gcloud compute forwarding-rules create http-content-rule \
--address=lb-ipv4-1\
--global \
--target-http-proxy=http-lb-proxy \
--ports=80
```
**Note:** A [forwarding rule](https://cloud.google.com/load-balancing/docs/using-forwarding-rules) and its corresponding IP address represent the frontend configuration of a Google Cloud load balancer. Learn more about the general understanding of forwarding rules from the [Forwarding rules overview](https://cloud.google.com/load-balancing/docs/forwarding-rule-concepts) guide.
Click **Check my progress** to verify that you've created an L7 Application Load Balancer.
Create an Application Load Balancer
Check my progress
## **Task 6. Test traffic sent to your instances**
1. On the Google Cloud console title bar, type **Load balancing** in the **Search** field, then choose **Load balancing** from the search results.
2. Click on the load balancer that you just created, **web-map-http**.
3. In the **Backend** section, click on the name of the backend and confirm that the VMs are **Healthy**. If they are not healthy, wait a few moments and try reloading the page.
4. When the VMs are healthy, test the load balancer using a web browser, going to `http://IP_ADDRESS/`, replacing `IP_ADDRESS` with the load balancer's IP address that you copied previously.
**Note:** This may take three to five minutes. If you do not connect, wait a minute, and then reload the browser.
Your browser should render a page with content showing the name of the instance that served the page, along with its zone (for example, `Page served from: lb-backend-group-xxxx`).
---
## Solution of Lab
%[https://www.youtube.com/watch?v=AkeamF3rtaE&ab_channel=QUICKGCPLAB]
```apache
curl -LO raw.githubusercontent.com/QUICK-GCP-LAB/2-Minutes-Labs-Solutions/refs/heads/main/Set%20Up%20Network%20and%20Application%20Load%20Balancers/gsp007.sh
sudo chmod +x *.sh
./gsp007.sh
```