Always On VPN Load Balancing with Loadbalancer.org

Recently, I had the opportunity to deploy the Loadbalancer.org load balancer as part of an enterprise Always On VPN deployment. In the past, I’ve published guidance for using F5 BIG-IP, Citrix ADC (formerly NetScaler), and Kemp LoadMaster, so in this post, I’ll provide guidance for configuring Loadbalancer.org for Always On VPN.

IKEv2

Open the Loadbalancer.org management console and follow the steps below to configure Always On VPN load balancing on the appliance.

Create Virtual Service

Create a layer 4 virtual service for IKEv2.

  1. Click Cluster Configuration.
  2. Click Layer 4 – Virtual Services.
  3. Click Add a new Virtual Service.
  4. Enter a descriptive name for the virtual service in the Label field.
  5. Enter the virtual IP address (VIP) for the service in the IP Address field.
  6. Enter 500,4500 in the Ports field.
  7. Select UDP from the Protocol drop-down list.
  8. Select NAT from the Forwarding Method drop-down list.
  9. Click Update.

Add Real Servers

Add real servers to the virtual service.

  1. Click Layer 4 – Real Servers.
  2. Click Add a new Real Server next to the IKEv2 virtual service.
  3. Enter a descriptive name for the real server in the Label field.
  4. Enter the IP address of the real server in the Real Server IP Address field.
  5. Click Update.
  6. Repeat these steps for each additional VPN server in the cluster.

SSTP

Follow the steps below to configure SSTP load balancing on the appliance.

Create Virtual Service

Create a layer 4 virtual service for SSTP.

  1. Click Cluster Configuration.
  2. Click Layer 4 – Virtual Services.
  3. Click Add a new Virtual Service.
  4. Enter a descriptive name for the virtual service in the Label field.
  5. Enter the virtual IP address (VIP) for the service in the IP Address field.
  6. Enter 443 in the Ports field.
  7. Select TCP from the Protocol drop-down list.
  8. Select NAT from the Forwarding Method drop-down list.
  9. Click Update.

Configure Virtual Service Health Check

Update the health check method for the SSTP virtual service.

  1. Click Layer 4 – Virtual Services.
  2. Click Modify on the SSTP virtual service.
  3. Select Negotiate from the Check Type drop-down list in the Health Checks section.
  4. Enter 443 in the Check Port field.
  5. Select HTTPS from the Protocol drop-down list.
  6. Enter /sra_{BA195980-CD49-458b-9E23-C84EE0ADCD75}/ in the Request to send field.
  7. Enter 401 in the Response expected field.
  8. Click Update.

Note: Using the Negotiate health check type for the SSTP monitor on Loadbalancer.org appliances requires version 8.13.0 or later. Administrators can use the External script option when using earlier releases of Loadbalancer.org appliances. An SSTP health check script for Loadbalancer.org can be found here.

Add Real Servers

Add real servers to the virtual service.

  1. Click Layer 4 – Real Servers.
  2. Click Add a new Real Server next to the SSTP virtual service.
  3. Enter a descriptive name for the real server in the Label field.
  4. Enter the IP address of the real server in the Real Server IP Address field.
  5. Click Update.
  6. Repeat these steps for each additional VPN server in the cluster.

Review

Once complete, click System Overview to view the overall health of your VPN servers.

Summary

The Loadbalancer.org appliance is an efficient, cost-effective, and easy-to-configure load-balancing solution that works well with Always On VPN implementations. It’s available as a physical or virtual appliance. There’s also a cloud-based version. It also includes advanced features such as TLS offload, web application firewall (WAF), global server load balancing (GSLB), and more. If you are looking for a layer 4-7 load balancer for Always On VPN and other workloads, be sure to check them out.

Additional Information

Loadbalancer.org Virtual Appliance

SSTP Health Check Script for Loadbalancer.org

Always On VPN Discord Channel

I’m excited to announce the launch of a brand-new Discord channel dedicated to administrators working with Always On VPN! Whether you’re a seasoned pro or just getting started, this community is designed to be your go-to hub for collaboration, troubleshooting, and staying up to date on all things Always On VPN. The channel was established by my good friend Leo D’Arcy, the creator of the popular Always On VPN Dynamic Profile Generator (DPC) software.

Why Discord?

Always On VPN is a powerful solution for secure, seamless remote connectivity, but managing it comes with its own set of challenges. From configuration quirks to deployment strategies, administrators often need a space to share insights, ask questions, and learn from one another in real-time. That’s where our new Discord channel comes in.

Community Forum

Discord offers a dynamic, user-friendly platform for instant communication and community building. Unlike forums or email threads, it’s a place where you can start a conversation, jump into live discussions, share resources, ask questions, share important insights or experiences, and much more.

Channels

Today, the Always On VPN Discord channel is part of the Microsoft Remote Access User Group Discord Server. It consists of multiple channels divided into the following topics.

General – This is a great place to introduce yourself and say hello to everyone!

DPC-Development – Here, you can ask questions about DPC, provide feedback, and suggest new features and functionality.

DPC-Chat – This channel is for administrators to discuss all things DPC, including deployment strategies, operation, support, and more.

Aovpn-Chat – If you’ve deployed Always On VPN but aren’t using DPC, this is your channel! Although DPC is fantastic, not everyone is using it. In this channel, you can submit questions and share general information about Always On VPN.

Gsa-Chat – We’ve also included a Microsoft Entra Global Secure Access channel for the new Microsoft Security Service Edge (SSE) solution, which includes Entra Private Access. This channel is pretty quiet right now. Hopefully, it will grow in the future!

DirectAccess-Chat – Yes, we realize some of you are still running DirectAccess, so there’s also a channel for you! Feel free to drop in and ask questions here, hopefully about migrating soon. 😉

Who Is This For?

This channel is open to anyone managing Microsoft secure remote access products. Whether you’re an IT administrator in a small business, an enterprise network engineer, or a consultant helping clients stay connected. If you’re working with Microsoft remote access technologies, this is the place to be!

Why Not Reddit?

Funny story: I tried to create an Always On VPN subreddit a few years ago. It lasted one day before it was banned! No reason was given, and I couldn’t get anyone from Reddit to respond. I answer questions ad hoc on Reddit all the time, but there’s no dedicated space for Always On VPN or Microsoft remote access in general.

How To Join

Joining our Discord channel is easy.

  1. Click this link.
  2. Set up your Discord account if you don’t already have one. It’s free and only takes a minute!
  3. Optionally, you can download the Discord app here.
  4. Say hello and introduce yourself in the #general channel.
  5. Explore the other channels, ask questions, give feedback, and share your expertise!

See You There!

Leo and I are on the forums daily, as are many other experienced Always On VPN administrators. We encourage you to share your expertise, ask questions, and help others along the way. The more we contribute, the stronger this resource becomes for everyone. Join us today!

Additional Information

Always On VPN Dynamic Profile Configurator (DPC)

DPC on GitHub

Always On VPN Security Updates October 2024

Microsoft has released the October 2024 security updates, and numerous issues may impact Always On VPN administrators. Although many CVEs affect Always On VPN-related services that are Remote Code Execution (RCE) vulnerabilities, none are critical this cycle.

RRAS Updates

This month, Microsoft has provided 12 updates for the Windows Server Routing and Remote Access Service (RRAS), commonly deployed to support Always On VPN deployments. Most of these CVEs involve overflow vulnerabilities (heap and stack), input validation weaknesses, and buffer over-read and overflow vulnerabilities. All are rated important, and there are no known exploits currently.

CVE-2024-38212

CVE-2024-38261

CVE-2024-38265

CVE-2024-43453

CVE-2024-43549

CVE-2024-43564

CVE-2024-43589

CVE-2024-43592

CVE-2024-43593

CVE-2024-43607

CVE-2024-43608

CVE-2024-43611

Related Updates

In addition to the updates above, Microsoft also released fixes for security vulnerabilities in various related services that are important to Always On VPN administrators.

Windows Network Address Translation (NAT)

The following CVEs address denial of service vulnerabilities in the Network Address Translation (NAT) service.

CVE-2024-43562

CVE-2024-43565

Certificate Services

Always On VPN administrators will also find updates for CVEs affecting various certificate services-related components.

CVE-2024-43545OCSP Denial of Service Vulnerability

CVE-2024-43541Simple Certificate Enrollment Protocol (SCEP) Denial of Service Vulnerability

CVE-2024-43544Simple Certificate Enrollment Protocol (SCEP) Denial of Service Vulnerability

Recommendations

Always On VPN administrators are encouraged to update systems as soon as possible. However, since none of the CVEs is rated Critical, updates can be applied during standard update windows.

Additional Information

Microsoft October 2024 Security Updates