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 for my motherboard). 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, determine 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)