A user of our sbRIO-based system is hooking his device to a link interface that does not support autoneg *AND* is running at 100 Mbit/s Full duplex. This will produce a duplex mismatch problem as the sbRIO NIC is always using autoneg...(in NI MAX we can only change the preferred mode/ability flag). The NIC on the sbRIO detects the speed (although I am not sure how stable that detection is expected to be(?)), but will as expected default to half duplex, not full. So, we want to disable autoneg on the sbRIO, and fix it to 100 Mbit/Full. I have seemingly succeeded in doing so by adding the highlighted line to the ifplugd.script: The question is, is this the/a correct way to do it on Linux RT, and/or is there a better/simpler way to do it? Setting it as an environmental (Ethtool_opt) variable in sysconfig seems to be another Linux-way to go, but I do not find where to apply that on Linux RT. Mads

NI Linux Real-Time Discussions

Correct way to disable link autoneg

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I seemed for a while to be able to avoid getting stuck in the no link error state after short link breaks...

At first I thought I had just needed to change the -d timer from-d0 to -d5 in /etc/ifplugd/ifplugd.conf. With a 5 second delay on the down-timer the idea was to never get into the unhandled case triggered by short breaks...and for a while it seemed to have worked. Then not. 😖

I suspect that this can all be related to the fixed link affecting auto-mdix though, so it is not really a software configuration issue.

Mads Toppe
Modbus Test Master - developed in LabVIEW