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Setting up a System w/ Wake-on-LAN and VNC?
andrebsd asks: "I'd like to make myself some sort of webpage where I could startup my system with 'Wake on Lan', and once it is started, use VNC to login. Once I'm done doing what I need the system for I would then like to shut it down again. I'm wondering how one might go about putting something like this together. VNC has various scripts for making that part work, but I haven't seen any scripts that can function as a 'Power on/Power off' button for a webpage. Thanks to anyone with any way of doing this." While there are helpful reference for Wake-on-LAN tools, how would you integrate all of these into a coherent system? How might one keep such a system (relatively) secure?
It'd be nice if you told us what kind of system you are planning on doing this to. Other hosts on the network that DON'T sleep? info, info, info!
I hold it, that a little rebellion, now and then, is a good thing. -- Thomas Jefferson
You'll need to lookup the precise specifications for WOL. Basically you simply send the MAC address three times to the target machine over UDP. Then the NIC wakes the computer up.
It's not very difficult to do this with a perl script or something similar that can be integrated into a web page.
Another alternative that may interest you if your target computer has access to a phoneline is "Wake on Ring". Some BIOS vendors (Abit was one) allow a modem to power on a PC after a specified number of rings.
Conformity is the jailer of freedom and enemy of growth. -JFK
Where is your "system"?
You do realize that Wake on LAN is a layer two protocol, right? I.e. it's an ethernet protocol that has nothing to do with IP, UDP, or TCP.
The webserver that is hosting this webpage will have to be on the same local area network [layer two] as your "system." So:
where the final arrow MUST be on the same local area network.The person who administers the webserver [the second to last point in the diagram] must give you sufficient rights to some daemon on that webserver so as to allow you to send out a layer two [ethernet] packet via that daemon. If you yourself are not the administrator of this webserver, the chances of you getting those kind of rights are between slim and none. The standard sandboxes, such as the Java sandbox, don't allow you to get anywhere near sending a layer two packet.
What's wrong with something simple? Throw a .htaccess in a directory with this (untested) script.2 3.123"; // or whatever
<html><body>
<?php
$machine="123.123.1
$connect="wakeonlan --wakeup $machine";
if($_REQUEST['connect']) {
exec($connect);
?>
Starting up <?=$machine?>.
<?php
} elseif(ping($machine)) {
?>
<?=$machine?> is up.
<?php
} else {
?>
<?=$machine?> is down. <a href="?connect=1">Start up</a>.
<?php
}
?>
</body></html>
Free Java games for your phone: Tontie, Sokoban
I use WOL to turn my Windows XP PC on by SSH'ing to my Linux server on the same LAN, then running the Linux WOL utility to turn the Windows PC on. Then I have the Terminal Services service running on the WinXP system on a non-default port where I can shut it down if I want to (using tsshutdn). It might also be possible to shut the system down remotely from the Linux system with Samba, but I've never tried that.
Trolls lurk everywhere. Mod them down.
I have a couple boxes on my network, one of which is a linux box that is "always-on". I have the SSH port (port 22) open to incoming connections from outside the network, and I have a VNC port open able to get to from outside the network, on the windows machine. I just ssh into my linux box, and run a simple perl script (I already recorded the NICs MAC address) to send the magic packet to the windows machine, give it a couple minutes, and then VNC on in to my windows machine. . .
YOU'RE WINNER !
Another lame blog
Maybe one piece of the puzzle of making Wake-on-LAN over VNC work would be to have a DSL modem, and some kind of always-on appliance that could be programmed to turn on the computer. The appliance must have an Internet address. This is the idea, but it is too expensive: Internet Power Switch. Maybe this would be better: 1-Port Serial Device Servers, but no price is listed.
You have a good basic idea. You don't want to leave the computer on all the time, but you would like to VNC the computer when you need it. Actually, I want that too.
All you need is a low-voltage switch with an Internet address. You can adjust the OS to turn on when the power switch is pressed and hibernate if the power switch is pressed, if the computer is already on. If you need a cold re-boot, you can run the shutdown command from VNC, using a time delay.
A switch with an Internet address need cost no more than $50. The question is, who sells such a switch?
I see lots of posts for using a local server that is always. I guess this will work for a lot of techie places... but what about everyone else?
Are there any cheap routers that can send a simple WOL message? Are there any that have been hacked so that someone can add this function?
At least the "standard AMD Magic Packet format" of WoL is ethernet-type 0x0842, not IP (0x0800). Instead of an IP-packet with dest- and source ip address it just contains repeatedly
"FF FF FF FF FF FF 00 11 22 33 44 55"
(if 00:11:22:33:44:55 is the target MAC). So it won't pass any routers, You have to do this in an ethernet-segment. Try
# ether-wake 00:11:22:33:44:55
and catch it with Your favorite sniffer.
It would be senseless to use IP for WoL, as the arp-table of the last router has already forgotten the MAC of the dest ip and cannot resolve via arp-request it as the destination host is sleeping. If You have no machine next to Your target, You're lost.
graf0z.
Everybody seems to have great solutions for that question, so let's make it tougher:
How about when I've got only one system, and it connects using PPPoE to the outside world... can anybody solve *that* one?
How about if pull out the power plug before I leave for work in the morning?