GSP062

Overview

This hands-on lab will show you how to create secure, high-throughput VPN and test the speed.

Secure communication between Google Cloud and other clouds or on-premises systems is a common, critical need. Fortunately, Google Cloud makes it easy for you to create a secure Internet Protocol security (IPsec) virtual private networks (VPNs) to achieve this goal. If a single tunnel does not provide necessary throughput, Google Cloud can smoothly distribute traffic across multiple tunnels to provide additional bandwidth.

Objectives

Create VPN

• Create a Virtual Private Cloud (VPC) named cloud to simulate your Google Cloud network, and a VPC named on-prem (on-premises) to simulate an external network.
• Create VPN gateways, forwarding rules, and addresses for the cloud VPC.
• Form a tunnel for the new VPN, and route traffic through it.
• Repeat the VPN creation process for the on-prem VPC, creating a second VPN.

Test VPNs

• Create a virtual machine (VM) using Compute Engine for throughput load testing.
• Test throughput speed of a single VPN using iperf.

Prerequisites

• Review and familiarize yourself with how to create a VPN using Google Cloud.
• Review the VPC network overview guide.

Task 1. Creating the cloud VPC

In this section, you will:

• Create a VPC to simulate your cloud production network.
• Allow common types of traffic to flow through the VPC.
• Create a subnet for deploying hosts.

1. After you start up Cloud Shell, create a custom VPC named cloud associated with your Google Cloud project by running the following:

This VPC allows you to use non-default IP addressing, but does not include any default firewall rules.

2. Run the following to enable SSH and icmp, because you'll need a secure shell to communicate with VMs during load testing:

3. Create a subnet within this VPC and specify a region and IP range by running:

In this solution, you'll be using 10.0.1.0/24 and the region.

Task 2. Creating the on-prem VPC

In this section create a simulation of your on-prem VPC, or any network you want to connect to cloud. In practice you'll already have resources here, but for the purpose of creating tunnels and validating configurations, follow these steps.

1. In Cloud Shell create a new custom subnet VPC associated with your project named on-prem by running:

2. Run the following to enable SSH and icmp for hosts in the on-prem VPC, because you'll need a secure shell to communicate with VMs during load testing:

3. Specify the subnet prefix for the region using the following command:

Task 3. Creating VPN gateways

Each environment requires VPN gateways for secure external communication. Follow these steps to create the initial gateways for your cloud and on-prem VPCs:

1. In Cloud Shell create a VPN gateway named on-prem-gw1 in the on-prem VPC and region:

2. Now create a VPN gateway named cloud-gw1 in the cloud VPC and region:

Task 4. Creating a route-based VPN tunnel between local and Google Cloud networks

The VPN gateways each need a static, external IP address so that systems outside the VPC can communicate with them. Now you'll create IP addresses and routes on the cloud and on-prem VPCs.

1. In Cloud Shell allocate the IP for the cloud-gw1 VPN gateway:

2. Then allocate the IP for the on-prem-gw1 VPN gateway:

3. Now store the gateway addresses so you won't have to look them up in later commands.

First, for the cloud-gw1 gateway:

Second, for the on-prem-gw1 gateway:

4. Now you'll create forwarding rules for IPsec on the cloud VPC. You'll need to create forwarding rules in both directions.

Forward the Encapsulating Security Payload (ESP) protocol from cloud-gw1:

Forward UDP:500 traffic from cloud-gw1:

Forward UDP:4500 traffic from cloud-gw1:

5. Use the same method to create firewall forwarding rules for the IPsec tunnel on the on-prem VPC. This step allows the IPsec tunnel to exit your firewalls:

Forward the ESP protocol from on-prem-gw1:

Forward UDP:500 traffic, used in establishing the IPsec tunnel from on-prem-gw1:

Forward UDP:4500 traffic, which carries the encrypted traffic from on-prem-gw1:

Ordinarily you would need to go generate a secret for the next step, where you create and validate the tunnels on-prem-tunnel1 and cloud-tunnel1. For details about how to create and securely store secrets, view the Secret Manager conceptual overview guide. For now just use the string "sharedsecret".

Create a tunnel for the local network on-prem-tunnel1, and for the cloud-based network cloud-tunnel1. Each network must have a VPN gateway, and the secrets must match. In the following two commands, where you would, in a production scenario, replace [MY_SECRET] with the secret you generated, replace it with "sharedsecret"

6. Create the VPN tunnel from on-prem to cloud:

7. Create the VPN tunnel from cloud to on-prem:

Now that you've created the gateways and built the tunnels, you need to add routes from the subnets through the two tunnels.

8. Route traffic from the on-prem VPC to the cloud 10.0.1.0/24 range into the tunnel:

9. Route traffic from the cloud VPC to the on-prem 192.168.1.0/24 range into the tunnel:

Task 5. Testing throughput over VPN

At this point, you've established a secure path between the on-prem and cloud VPCs. To test throughput use iperf, an open-source tool for network load testing. To test, you'll need a VM in each environment, one to send traffic and the other to receive it, and you'll create them next.

Single VPN load testing

Now you'll create a virtual machine for the cloud VPC named is cloud-loadtest. This example uses a Debian Linux image for the OS.

1. Run the following:

2. Create a virtual machine for the on-prem VPC named on-prem-loadtest. This example uses the same Debian image as in the cloud VPC. Omit this step if you have existing resources.

Run the following:

3. SSH into each VM, using the Console or command line, and install a copy of iperf with the following command line:

4. On the on-prem-loadtest VM, run this command:

You have created an iperf server on the VM that reports its status every 5 seconds.

5. On the cloud-loadtest VM, run this command:

This creates an iperf client with twenty streams, which will report values after 10 seconds of testing.

Trouble shooting for the issues you may face

1. While creating tunnels for the local network, if you forgot to replace [MY_SECRET] with "sharedsecret".

You can delete the created VPN tunnels by following command:

• replace [tunnel-name] with name of the tunnel
• replace [region] with the region which you specified while creating tunnel.

2. If you are having trouble with the section single VPN load testing:

• Make sure you installed iperf on both VMs.

• In case of connection refused error, verify that:

  • Firewall rules for created networks (tcp:5001)
  • The server is running properly on on-prem-loadtest
  • You are trying to connect to the server via cloud-loadtest

3. If you are trying to see the forwarding rules that you created in the Console:

• In the Navigation menu go to the Networking section.
• Click on Network Connectivity > VPN.
• Click on the Cloud VPN Gateway to view the Cloud VPN Gateway details page.

Congratulations!

Take your next lab

Continue with Cloud CDN, or check out these suggestions:

• Web Security Scanner: Qwik Start
• Cloud IAM: Qwik Start

What's next

• Review Google Cloud Router to enable Border Gateway Protocol (BGP) and increase fault tolerance.
• Review Google Cloud Interconnect for other interconnection options.
• Monitor the VPN gateways with Google Stackdriver.
• Try out other Google Cloud features for yourself. Have a look at our tutorials.

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Manual Last Updated February 25, 2025

Lab Last Tested February 25, 2025

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