Restriction when using ADC on transparent mode

[T2K]

Hi,

I am planning to use ADC in transparent mode and would like to know if there are any limitations compared to L3 mode. I couldn’t find clear information on this.

For example, are there fewer load-balancing methods or health check options available in transparent mode than in L3 mode?

Regards,

 # https://docs.fortinet.com/document/fortiadc/7.2.4/handbook/592141/transparent-mode

[Stephen_G]

Hello,

Thank you for using the Community Forum. I will seek to get you an answer or help. We will reply to this thread with an update as soon as possible.

Thanks,

[Stephen_G · Accepted solution]

Hi T2K,

I obtained the following information - please let me know if it helps.

In transparent mode, the FortiADC operates at Layer 2, bridging traffic without modifying IP addresses. Here are some considerations and potential limitations when using FortiADC in transparent mode compared to Layer 3 mode:

1. Load Balancing Methods:

Transparent mode primarily focuses on Layer 2 operations, so some advanced Layer 3 load-balancing methods might not be available. However, basic load-balancing functionalities should still be supported.

2. Health Check Options:

While health checks are generally supported, the range of available health check methods might be more limited compared to Layer 3 mode. It's important to verify the specific health check capabilities in the transparent mode configuration guide.

3. Network Configuration:

Transparent mode allows you to insert the FortiADC into an existing network without changing IP addresses, which simplifies deployment but may limit some advanced routing capabilities.

4. Traffic Handling:

All traffic that FortiADC does not support can pass through the soft-switch interface without interruption, but supported traffic like LLDB and DHCP needs to be terminated.

5. STP Participation:

The FortiADC soft-switch does not participate in the Spanning Tree Protocol (STP), and all STP BPDUs are forwarded directly. For detailed information on specific features and limitations, refer to the FortiADC Transparent Mode Configuration Guide: https://docs.fortinet.com/document/fortiadc/7.4.4/handbook/592141/transparent-mode