Unable to launch the ISG device's console using ISGAC: "An unexpected server error occurred"

Products

• Management Center - VA
• SSP

Issue/Introduction

When attempting to launch the Integrated Secure Gateway Admin Console (ISGAC) for a managed ISG device via the Management Center (MC), the console fails to load with the error: "Failed to start console session: An unexpected server error occurred".




- Notably, these errors occur even when the ISG device has been successfully showing healthy connectivity with the Management center.

Environment

ISG device (SSP) integrated into the Management center for management using the ISG admin console(ISGAC) and might show healthy connectivity.
The ISG device is configured with a max-concurrent login limit.

Cause

The Management Center requires multiple simultaneous SSH sessions in the background to effectively poll, monitor, and manage an ISG appliance. When an administrator attempts to launch the ISG Admin Console through the MC GUI, it requires additional backend connections to establish the hosted console session.

If the max-concurrent-logins parameter within the ISG device's management authentication settings is set too low (e.g., restricted to 1 or 2 concurrent logins), the Management Center's standard operations will exhaust the allowed session limit.

Resolution

To resolve this issue, you must increase the maximum concurrent login limit directly on the ISG appliance via CLI to accommodate the Management Center's multi-session requirements.

ISG> enable
ISG# configure terminal
ISG(config)# authentication management max-concurrent-logins <max-logins>

Additional Information

Another Symptom of the issue: The ISG device abruptly closes the SSH connection immediately after successfully validating user credentials, without logging or displaying any explicit error messages.