3
6
Programming LAN Bypass
Network Application Platforms
Appendix
D
Programming Generation 2
and 3 LAN Bypass
Lanner Generation 3 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
states:
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
And the 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.
Please refer to
Please refer to the LAN_Bypass_Watchdog folder on the
Driver and Manual CD.
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
.
Fro a description of the physical LAN ports equipped with
this function, refer to
Lanner Generation 2 Bypass
Unlike Lanner Generation 3 bypass, Generation 2 bypass is
configured through the BIOS menu as shown below:
There are two ways to enable the bypass on the system:
1. The LAN bypass can be turned on or off in two system
