Wake on LAN over different VLANS
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OK… troubleshooting time I suppose.
You need to find a utility that will send a wake-on-lan packet to your desired IP address… (the broadcast address).
Then,
Go on site and see if you can broadcast a WOL packet and see if computers start up. If it works, then your switches / router configurations are to blame.If it doesn’t work… maybe make sure WOL is enabled on those computers… maybe try to WOL an individual client and see if that works.
Report back and we will go from there.
I’d recommend trying this one:
http://sourceforge.net/projects/aquilawol/
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@Wayne-Workman I just downloaded this program and tested it exactly how you had asked and the computer wakes up perfectly fine. I then turned it off and attempted to wake on lan again from FOG and again to no avail. So you’re saying it’s a switch/router config thats to blame but I am not sure where that could be.
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One thing you can try is sending the packet from the command line with wakeonlan
wakeonlan 28:D2:44:0C:D9:9B Sending magic packet to 255.255.255.255:9 with 28:D2:44:0C:D9:9BDo you have wireshark? If so set the filter to wol and see if you get a packet, if not your switches may be blocking it.
Here were the relevent Cisco commands I had to set on our 4500:
***fogserver vlan*** interface Vlan2 ip helper-address 10.2.255.255 ! ***high network vlan*** interface Vlan1 ip helper-address 10.1.0.119 ip directed-broadcast 101 ! ip forward-protocol udp echo ip forward-protocol udp discard access-list 101 permit udp host 10.1.0.119 any eq echo access-list 101 permit udp host 10.1.0.119 any eq discard -
@cml
I attempted to do that and by the image you see I tried exactly the same thing and the computer doesnt turn on.
I have wireshark but have never used the program to know how to filter to wol -
In wireshark first select your connection and then click start
Once started type wol into the filter box and click on apply.
This is what it looks like when I send a wol:
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Ok i did exactly what you said. the top one is from a computer in the 10.1.x.x address and the bottom one which is the one that worked is from the 10.2.x.x address.
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The top one is on the same subnet as your fog server correct?
Try running wireshark on the bottom machine (i assume it is on the same subnet as your target), but send the wol from your fog server.
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@cml You are correct, the top one is on the same vlan as the fog server.
I just ran wireshark on the bottom machine and ran wol from the fog server and wireshark didnt pick anything up
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Your switch is not forwarding the packets across subnets. Do you know what manufacture/model your L3 device is?
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I thought this article was pretty good.
http://theithollow.com/2012/04/how-to-broadcast-across-subnets/ -
@cml My layer 3 device is Nortel 8010
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Not familiar with Nortel’s configuration, but there is this post:
http://blog.michaelfmcnamara.com/2009/02/wake-on-lan-and-directed-broadcast/
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@cml I double checked and we already enabled that portion of the switch and still nothing. But I did find a configuration on the switch from broadcast addresses and nothing is listed. Do you think if I entered the broadcast address there,the passport would then allow the packets to pass through the VLANs?
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@szecca1 Try it and see.
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@Wayne-Workman I put an email to my company because I didn’t want to try it and cause my entire network to go down. As soon as I hear from them I will give it a try
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@szecca1 Better yet, see if you can get in touch with a Nortel person and see what they say about it. Or search their website for information.
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@Wayne-Workman With this situation and me not being the network admin, my company would probably prefer me going directly to them first and then if possible calling Nortel. I will definitely keep you guys updated.
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@Wayne-Workman said:
@szecca1 Better yet, see if you can get in touch with a Nortel person and see what they say about it. Or search their website for information.
I think you are saying that FOG requires that broadcasts be allowed to travel across the router to other VLANs.
This makes no sense - and even if it could be done - would not be advisable.
That’s what I’m being told, does this sound correct? -
@szecca1 said:
@Wayne-Workman said:
@szecca1 Better yet, see if you can get in touch with a Nortel person and see what they say about it. Or search their website for information.
I think you are saying that FOG requires that broadcasts be allowed to travel across the router to other VLANs.
This makes no sense - and even if it could be done - would not be advisable.
That’s what I’m being told, does this sound correct?You came to us with questions about how this is done, and we’ve helped you to the best of our abilities to troubleshoot, identify the problem, and guide you to accomplish what you’re wanting. It’s not our place to say what’s advisable and what’s not for you. Those kinds of decisions should be made by you and your network team.
We’re just here to help you do what you want, to help solve problems, etc.
But, I’ll tell you, it sounds like your network team don’t fully understand how the WOL plugin works, and I’ll tell you that YES, it can be done. And while the packet is a broadcast packet, it’s a packet destined for another network. It’s not broadcast throughout it’s source network, only it’s destination network. The router needs only to forward it, like we’ve pointed out. When it’s broadcast at the destination network, when those broadcast packets hit the router, because the destination network matches the source network, the router ignores it.
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There is one alternative that I thought of…
You could use dedicated relays.
Relays are generally used to encapsulate a UDP packet (or any packet) into a TCP packet, send it to a relay on another network, then the receiving relay would then decapsulate the packet back to UDP, and then send it out.
I’ve seen this used for emergency broadcast systems before, it works well. I’m sure there are several software solutions that do it, both free and paid.
Then, you could just point the WOL plugin to the local relay. Ofcourse, this is just an alternative if your network team just doesn’t want to make a change. You could setup relays without help from the network guys. It’s not ideal and would require you to run a relay on some computer on each network (like a server)… but it’d work.
