(Update 3.ix.2011: This content is from 2006. I don't have the hardware any more so I cannot reproduce what is described here. I am keeping this around for posterity in case it might be of use to others.) Recently I've been wrestling with WOL for one of my linux servers. I found a WOL client called `etherwake`, which installs just fine in OpenDebianSlug using the command `apt-get install etherwake`. However, I found that I was having problems on the other end. I noticed that if I switch off the computer using the front power switch at the GRUB boot menu, I could wake the machine using etherwake, whereas if I use `shutdown -h now` from within linux, nothing happens. The tell-tale sign is that the port light on my 3Com router/switch is lit in the first instance, and dark in the second. A bit of googling around suggested that this is a common problem. The explanation was something along the lines of "linux shuts down your network card on OS shutdown". (For the pedantic, this should be rephrased as "most linux distributions shutdown the network card on shutdown"). The Gentoo Wiki's page on WOL suggested [removing the `-i` option from `halt`][gentoo]. Starting from this, I managed to get my machine to shutdown and be WOL'able! ## Server config My machine is running Fedora Core 4, though these change would likely work for other versions of Fedora and Redhat/CentOS. I changed the script `/etc/init.d/halt` so that the last few lines were changed from HALTARGS="-i -d" [ -f /poweroff -o ! -f /halt ] && HALTARGS="$HALTARGS -p" exec $command $HALTARGS to HALTARGS="-d" [ -f /poweroff -o ! -f /halt ] && HALTARGS="$HALTARGS -p" /usr/sbin/ethtool -s eth0 wol g sleep 5 # this pause seems to be important! exec $command $HALTARGS Note the removal of `-i` from `HALTARGS` and the extra `ethtool` invocation before the last `exec` command. ## Client config This is the easy part. I created a file called `/etc/ethers` to map names to my MAC addresses: 00:20:ED:5A:00:2B fried 00:11:09:24:1C:8B white Now to wake up `fried`, all I need to do is type the following command: sudo etherwake fried and `fried.rice` wakes up! [gentoo]: http://gentoo-wiki.com/Wake_on_lan "Gentoo WOL"