arrow_back

Building a High-throughput VPN

Join Sign in

Building a High-throughput VPN

1 hour 7 Credits

GSP062

Google Cloud self-paced labs logo

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

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:

gcloud compute networks create cloud --subnet-mode custom

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

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

gcloud compute firewall-rules create cloud-fw --network cloud --allow tcp:22,tcp:5001,udp:5001,icmp
  1. Create a subnet within this VPC and specify a region and IP range by running:

gcloud compute networks subnets create cloud-east --network cloud \ --range 10.0.1.0/24 --region us-east1

In this solution, you'll be using 10.0.1.0/24 and the us-east1 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:

gcloud compute networks create on-prem --subnet-mode custom
  1. 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:

gcloud compute firewall-rules create on-prem-fw --network on-prem --allow tcp:22,tcp:5001,udp:5001,icmp
  1. Specify the subnet prefix for the region using the following command:

gcloud compute networks subnets create on-prem-central \ --network on-prem --range 192.168.1.0/24 --region us-central1 Note: In this example, you assign `192.168.1.0/24` to the `us-central1` region. Create two custom VPCs with subnetworks and firewall rules.

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 us-central1 region:

gcloud compute target-vpn-gateways create on-prem-gw1 --network on-prem --region us-central1
  1. Now create a VPN gateway named cloud-gw1 in the cloud VPC and us-east1 region:

gcloud compute target-vpn-gateways create cloud-gw1 --network cloud --region us-east1

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:

gcloud compute addresses create cloud-gw1 --region us-east1
  1. Then allocate the IP for the on-prem-gw1 VPN gateway:

gcloud compute addresses create on-prem-gw1 --region us-central1
  1. Now store the gateway addresses so you won't have to look them up in later commands.

First, for the cloud-gw1 gateway:

cloud_gw1_ip=$(gcloud compute addresses describe cloud-gw1 \ --region us-east1 --format='value(address)')

Second, for the on-prem-gw1 gateway:

on_prem_gw_ip=$(gcloud compute addresses describe on-prem-gw1 \ --region us-central1 --format='value(address)')
  1. 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:

gcloud compute forwarding-rules create cloud-1-fr-esp --ip-protocol ESP \ --address $cloud_gw1_ip --target-vpn-gateway cloud-gw1 --region us-east1

Forward UDP:500 traffic from cloud-gw1:

gcloud compute forwarding-rules create cloud-1-fr-udp500 --ip-protocol UDP \ --ports 500 --address $cloud_gw1_ip --target-vpn-gateway cloud-gw1 --region us-east1

Forward UDP:4500 traffic from cloud-gw1:

gcloud compute forwarding-rules create cloud-fr-1-udp4500 --ip-protocol UDP \ --ports 4500 --address $cloud_gw1_ip --target-vpn-gateway cloud-gw1 --region us-east1
  1. 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:

gcloud compute forwarding-rules create on-prem-fr-esp --ip-protocol ESP \ --address $on_prem_gw_ip --target-vpn-gateway on-prem-gw1 --region us-central1

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

gcloud compute forwarding-rules create on-prem-fr-udp500 --ip-protocol UDP --ports 500 \ --address $on_prem_gw_ip --target-vpn-gateway on-prem-gw1 --region us-central1

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

gcloud compute forwarding-rules create on-prem-fr-udp4500 --ip-protocol UDP --ports 4500 \ --address $on_prem_gw_ip --target-vpn-gateway on-prem-gw1 --region us-central1 Create two VPN gateways and necessary forwarding rules.

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"

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

gcloud compute vpn-tunnels create on-prem-tunnel1 --peer-address $cloud_gw1_ip \ --target-vpn-gateway on-prem-gw1 --ike-version 2 --local-traffic-selector 0.0.0.0/0 \ --remote-traffic-selector 0.0.0.0/0 --shared-secret=[MY_SECRET] --region us-central1
  1. Create the VPN tunnel from cloud to on-prem:

gcloud compute vpn-tunnels create cloud-tunnel1 --peer-address $on_prem_gw_ip \ --target-vpn-gateway cloud-gw1 --ike-version 2 --local-traffic-selector 0.0.0.0/0 \ --remote-traffic-selector 0.0.0.0/0 --shared-secret=[MY_SECRET] --region us-east1

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

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

gcloud compute routes create on-prem-route1 --destination-range 10.0.1.0/24 \ --network on-prem --next-hop-vpn-tunnel on-prem-tunnel1 \ --next-hop-vpn-tunnel-region us-central1
  1. Route traffic from the cloud VPC to the on-prem 192.168.1.0/24 range into the tunnel:

gcloud compute routes create cloud-route1 --destination-range 192.168.1.0/24 \ --network cloud --next-hop-vpn-tunnel cloud-tunnel1 --next-hop-vpn-tunnel-region us-east1 Create two VPN tunnels.

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.

Note: If you have an existing project, feel free to omit this step and use existing resources. Bandwidth for a VM is 2 Gbps * vCPUs, so you'll want a 4 vCPU minimum.
  1. Run the following:

gcloud compute instances create "cloud-loadtest" --zone "us-east1-b" \ --machine-type "n1-standard-4" --subnet "cloud-east" \ --image-family "debian-11" --image-project "debian-cloud" --boot-disk-size "10" \ --boot-disk-type "pd-standard" --boot-disk-device-name "cloud-loadtest"
  1. 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:

gcloud compute instances create "on-prem-loadtest" --zone "us-central1-a" \ --machine-type "n1-standard-4" --subnet "on-prem-central" \ --image-family "debian-11" --image-project "debian-cloud" --boot-disk-size "10" \ --boot-disk-type "pd-standard" --boot-disk-device-name "on-prem-loadtest"
  1. SSH into each VM, using the Console or command line, and install a copy of iperf with the following command line:

sudo apt-get install iperf
  1. On the on-prem-loadtest VM, run this command:

iperf -s -i 5

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

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

iperf -c 192.168.1.2 -P 20 -x C

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

Create two VMs and install iperf via ssh.

Trouble shooting for the issues you may face

Note: This is not part of lab instructions.
  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:

gcloud compute vpn-tunnels delete [tunnel-name] --region [region]
  • replace [tunnel-name] with name of the tunnel

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

  1. 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
  1. 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 Hybrid Connectivity > VPN.

  • Click on the Cloud VPN Gateway to view the Cloud VPN Gateway details page.

Congratulations!

Finish your quest

These self-paced labs are part of the Network Performance and Optimization and Security & Identity Fundamentals quests. A quest is a series of related labs that form a learning path. Completing a quest earns you a badge to recognize your achievement. You can make your badge or badges public and link to them in your online resume or social media account. Enroll in any quest that contains this lab and get immediate completion credit. Refer to the Google Cloud Skills Boost catalog for all available quests.

Take your next lab

Continue your quest with Cloud CDN, or check out these suggestions:

What's next

Google Cloud training and certification

...helps you make the most of Google Cloud technologies. Our classes include technical skills and best practices to help you get up to speed quickly and continue your learning journey. We offer fundamental to advanced level training, with on-demand, live, and virtual options to suit your busy schedule. Certifications help you validate and prove your skill and expertise in Google Cloud technologies.

Manual Last Updated August 15, 2022

Lab Last Tested January 25, 2021

Copyright 2022 Google LLC All rights reserved. Google and the Google logo are trademarks of Google LLC. All other company and product names may be trademarks of the respective companies with which they are associated.