WSS Agent reconnects when downloading files from back end server

Products

• Cloud Secure Web Gateway - Cloud SWG

Issue/Introduction

macOS users running WSS Agent to access internet sites via Cloud SWG.

Some users report connection failures/drops when trying to download builds from AWS via CLI.

Users reporting the issue are on the same Wifi network - tethering macOS device to their phone and going out a mobile network did not show any errors. Issue not seen with any remote users.

WSS Agent diagnostic logs show "ec:55 error" at the time the download connections fail - indicating a macOS buffer issue.

 

Environment

macOS WSS Agent.

Wifi network.

Downloading large files from Web server.

Cause

The processing of requests via Wifi network appears to be slower than wired network that makes the issue more visible.

The WSS Agent was too aggressive handling this macOS error code and the updated agent is more forgiving.

Resolution

Apply WSS Agent 9.8.2 and greater.

With this WSS Agent version, the WSS Agent does not automatically RECONNECT when a buffer overload condition is encountered. Instead, the requests are dropped and the TCP/IP stack will simply trigger a re-request of the missing TCP segments.