Wake on LAN over different VLANS

[Tom Elliott]

You likely need to allow udp-broadcast-forwarding on your switches. At the very least, it needs to be enabled for the routing switch. The way to do this varies depending on the switch. HP Procurve allows for udp-broadcast-forwarding on (I think)

[szecca1]

@Tom-Elliott We already did that thinking it was a switch problem before doing this plug in

[Tom Elliott]

@szecca1 are you 100% sure that 10.2.255.255 is that networks broadcast address?

[szecca1]

@Tom-Elliott I worked with @Wayne-Workman and he helped me figure that out by converting an IP address into that. Previous posts go through it and thats what we came to the conclusion it is.

[Tom Elliott]

What is the subnet mask of your network? Class A, B, C?

[szecca1]

@Tom-Elliott Subnet mask is 255.255.0.0, class B

[Wayne Workman]

@Tom-Elliott said:

@szecca1 are you 100% sure that 10.2.255.255 is that networks broadcast address?

If the info he gave me is correct, I can assure that what we came up with is correct, but feel free to doublecheck my work using third party tools: http://www.subnetonline.com/pages/subnet-calculators/ip-subnet-calculator.php

[szecca1]

@Wayne-Workman As long as all you needed was a random IP address and the subnet that info is correct. The only thing weird is the website you sent is saying we are a class A even though we are a class B.

[Tom Elliott]

That’s often the case class a class B classy are usually directed by the first octet one through 126.whatever is considered class a, 128.whatever through 191.whatever is considered class b,192 up is class c

[szecca1]

@Tom-Elliott ok that makes sense, and I ran another test and still wake on lan is not working. At this point I am not sure what to do. The imaging works perfectly but the clients have to be on in order for the imaging to go through, obviously.

[Wayne Workman]

Your public IP might be a Class B address…

But internally, you have Class A addressing via NAT.

[szecca1]

@Wayne-Workman “The three default subnet masks are 255.0.0.0 for Class A, 255.255.0.0 for class B, and 255.255.255.0 for Class C.”

From this my impression is we have a class B subnet mask but I could be wrong, but I dont think this matters as whichever class it is, wake on lan isnt working lol

[Wayne Workman]

@szecca1

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/

[szecca1]

@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.

[cml]

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:D9:9B

Do 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

[szecca1]

@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

[cml]

@szecca1

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:

[szecca1]

@cml

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.

[cml]

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.

[szecca1]

@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