Appendix C: Programming Generation; Lan Bypass - Lanner NCA-5210 User Manual

APPENDIX C: PROGRAMMING GENERATION 3

LAN BYPASS

The bypass function is used to link two independent Ethernet ports when the system crashes or powers off.
This means if your system is equipped with a LAN Bypass function, a condition in your system will not
interrupt your network traffic. Different from the previous two generations (Gen1 and Gen2), the Lanner
Bypass Gen 3 employs a programming method to control the bypass function by software. There are typically
two communication status for the bypass function, one is "Normal" and another is "Bypass" status.
Furthermore, the Lanner Bypass software is capable to control the bypass status in the following 3 instances.
1. When the system powers off, it can be forced to enable the LAN Bypass function.
2. When the system is in the just-on state which is a brief moment when it powers up.
3. When the system is running
Please refer to the LAN_Bypass_Watchdog folder on the Driver and Manual CD.
Lanner bypass possess the following features:
1. Communication through SMBUS (I2C)
2. Independent bypass status control for each pair up to a total of 4 pairs
3. Lanner Bypass Modules can bypass systems Ethernet ports on a host system during three instances: Just-
on (Just-on is the brief moment when the internal power supply turns on and booting process starts), System
off, or upon software request (during run-time).
4. Software programmable bypass or normal mode
5. Software programmable timer interval:
- JUST-ON watchdog timer, used during JUST-ON, has timer setting of 5~1275 seconds of timer interval.
- Run-Time watchdog timer, used during run-time, has setting of 1~255 seconds of timer interval.
6. Multiple Watchdog Timers:
-Two for run-time: It is designed to give you a more variety of controls of the bypass on port basis. By using
dedicated watchdogs for different pairs of bypass, you have the flexibility to manage the bypass status for
them differently.
-One for just-on: It is designed to give you the precise control of the bypass during this phase. You can use
this timer to delay enabling the bypass in just-on state.
For sample LAN bypass code and the Bypass Manual, see the LAN_Bypass folder on the Driver and Manual
CD or the Lanner Support Website at http://www.lannerinc.com/download-center/ and browse the download
center and look for Lanner LAN Bypass Watchdog User Manual under the Accessories folder.
For a description of the physical LAN ports equipped with this function, refer to Front Panel Features in
Chapter1 Introduction.
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