WSL2 outbound connections with WSS Agent don't work when set to Mirrored mode

Products

• Cloud Secure Web Gateway - Cloud SWG

Issue/Introduction

There are few networking setups that can be configured on WSL2:

https://learn.microsoft.com/en-us/windows/wsl/networking

When changing the configuration to mirrored mode the outbound connection handshakes fail making the client machine not to receive the SYN, ACK from the upstream. 

That makes the client to start retransmitting the initial SYN from the initial handshake while the agent keeps retransmitting the SYN, ACK response from the upstream without getting it delivered to the client machine.

Environment

Client machine with WSS Agent  redirects traffic of interest from user devices to the Symantec Enterprise Cloud.

Cause

Agent won't work in mirrored mode due to a limitation from the OS side because its limited hooking ability that the it provides to the drivers. The issue is not from the not WSS Agent side.

 

 

 

Resolution

Recommended to use default NAT mode instead.