Error: LDAPS Authentication Fails on First Try in DX NetOps Classic

Products

• Network Observability
• Spectrum

Issue/Introduction

LDAPS authentication intermittently fails on the initial attempt but succeeds on the second try ․​​​​‌​‍

ERROR MESSAGE: "LDAPS Authentification sometimes works after second try"

SYMPTOMS:

• First login attempt via LDAPS fails․

• Immediate second login attempt succeeds ․

CONTEXT: Occurs during user authentication via LDAPS routed through a load balancer or traffic controller TCP profile ․

IMPACT: Users experience intermittent login failures requiring manual retries ․

Environment

 

• OS: Linux

• DX Netops Spectrum: 25․4․6

• Component: Network Observability

• Network: Load Balancer / Proxy (TCP Profile)

 

Cause

The network load balancer TCP profile drops idle connections before the application expects, causing the first authentication packet to fail while the connection is rapidly re-established for the second attempt ․

Resolution

PREREQUISITES:

• Administrator access to the network load balancer (e․g․, F5 Local Traffic Manager)

• Maintenance window if required by network policy

STEPS:

1․ UPDATE TCP PROFILE IDLE TIMEOUT

Path: Local Traffic >> Profiles : Protocol : TCP >> [tcp-profile-name]-default

Set the Timer Management configuration: Idle Timeout: 300 seconds

EXPECTED: Idle connections remain open longer, preventing the authentication server from dropping the initial bind request ․

VERIFY SUCCESS:

• Perform an initial LDAPS login after a period of inactivity to confirm it succeeds on the first try․