Hi,
Try using the command as root since you want to make system changes. Look at this for a useful guide;
Quote:
man ethtool;
NAME
ethtool - query or control network driver and hardware settings
SYNOPSIS
ethtool devname
ethtool -h|--help
ethtool --version
ethtool -a|--show-pause devname
|
Be sure to look at all the 'man ethtool' to understand available options.
Hope this helps.
Have fun & enjoy!