Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required.

It so happens that I have a NIC that is only able to establish a connection with the current network when auto negotiation is set to false. In windows, this can be achieved rather easily by changing the NIC properties via Device Manager. Currently I am only able to do so in Ubuntu (10.04 if that matters) via the following after login:

sudo ethtool -s eth0 autoneg off speed 100 duplex full

sudo service network-manager restart

PS: I have read reports from ubuntu forums that it may be necessary to remove network-manager and only use /etc/network/interfaces for configuration, but I intend to do so only as a last resort. I would also appreciate it if someone can add auto-negotiation ethtool to the list of tags.

share|improve this question
add comment

2 Answers

I've had better results putting ethtool scripts in /etc/network/if-up.d . According to Network Manager documentation, scripts in /etc/NetworkManager/dispatcher.d will be run after NM 'fiddles with interfaces'. On my 12.04 system, the only script is 01ifupdown, which will then run scripts in /etc/network/if-up.d (also /etc/network/if-post-down.d).

This sequence of events seems to happen well after the login screen appears on my system. I've found many occurrences of the following line in the system log which may explain what is causing the delay:

NetworkManager[871]: (eth0): carrier now OFF (device state 100, deferring action for 4 seconds).

share|improve this answer
add comment
up vote 0 down vote accepted

There seems to be no way to do it within Network Manager. Editing /etc/network/interfaces on the other hand is clumsy and causes delays in later editions of Ubuntu like 12.04 (see this and this). In the end the solution offered here turns out to be best (for now), by adding the ethtool command to rc.local:

sudo gedit /etc/rc.local

ethtool -s eth0 autoneg off speed 100 duplex full    # put this above 'exit 0'
share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.