tunnel server losing client connections over time

Products

• DX Unified Infrastructure Management (Nimsoft / UIM)

Issue/Introduction

A tunnel server has a number of tunnel clients connected.

Over time, it appears that some of the expected clients are no longer connected.

Restarting the tunnel server or the client hub brings the client back.

Environment

DX UIM - 23.4.6 and prior

Cause

SSL handshake latency

Resolution

Tunnel clients frequently close and re-open sessions which requires a new SSL handshake to be performed.

In some environments, due to latency, load, or other factors, the handshake takes too long to complete, and the client fails to open new sessions, eventually causing the client to be completely disconnected from the tunnel server.

In many cases, restarting the server or client may help as a temporary workaround.

In DX UIM 23.4.7 (CU7) a new configuration option will be added to the hub to extend the timeout for SSL handshakes, which is currently harcoded.

Tentative release date for CU7 is March/April 2026.