I got tired of running down the stairs to my mythbox to power it on whenever i wanted to access it from my desktop. I figured, it would be nice to be able to powerup my mythbox using wake-on-lan (wol). Wake-on-lan works by broadcasting a 'magic packet' over the network. This packet contains a MAC address. The network card examines the packet, determines whether the MAC address matches its own and if so, starts the computer. I used an Epia M10000 with Fedora Core 4.
If you have a network card that supports wake-on-lan, you can powerup your mythbox by sending it a 'magic packet' over the network. Here's what i did:
First, find out whether your network card supports wol:
# ethtool eth0 Settings for eth0: Supported ports: [ TP MII ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full Supports auto-negotiation: Yes Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full Advertised auto-negotiation: Yes Speed: 100Mb/s Duplex: Full Port: MII PHYAD: 1 Transceiver: internal Auto-negotiation: on Supports Wake-on: pumbg Wake-on: g Current message level: 0x00000001 (1) Link detected: yes
The 'g' in Supports Wake-on: pumbg indicates that wake-on-lan by using a 'magic packet' is indeed supported. Next, you need to make sure that wake-on-lan support is enabled in the BIOS (although, this does not seem to be necessary on my Epia M10000). In addition, you need to tell your network card to enable wake-on-lan:
# ethtool -s eth0 wol g
Since after rebooting Wake-on will be reset, you might what to add it to /etc/rc.local:
# echo 'ethtool -s eth0 wol g' >> /etc/rc.local
Now turn off you mythbox and send it a 'magic packet'.
Sending 'magic packet' to wake up your mythbox
You will need a wake-on-lan client to send 'magic packets' over your network. First, you need to known the MAC address of the machine you what to power on:
Turn off you mythbox and from another computer execute the following command (replacing the MAC address with the one you just found). I used a wake-on-lan client from Sourceforge.
$ wol 00:4F:49:07:0B:5F
- http://ahh.sourceforge.net/wol/ (wake-on-lan client + additinal information)
- http://dag.wieers.com/packages/wol/ (wol packages for RedHat and Fedora)
- http://www.die.net/doc/linux/man/man8/ethtool.8.html (man page for ethtool)
- http://www.sourceforge.net/projects/gkernel/ (gkernel package that contains ethtool)