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New Member

Wake On Lan Questions


Can anyone provide how Wake On Lan works, i have to implement it for a Client and i can`t find the right info on the internet (i`m doing the network part) this doc is quite simple if you are just traversing one Layer 3 domain so what if i had to go through more hops

Any help will be really apreciate it

Everyone's tags (3)

Wake On Lan Questions

Do this help you:

I have no experience on WoL but If you need maybe we find a solution with the information in the other threads.


pls. rate if helpful

New Member

Wake On Lan Questions

Hi Sebastien

I have checked all the discussion but couldn`t find the answer since it`s quite confusing a bit (some are sayin that ip helper is needed but i doubt it ... i`ll do the test tomorrow and keep you posted ... otherwise i`ll see if i can flip it to multicast on the SCCM instead of direct broadcast

Wake On Lan Questions

I remember one thing..

I use ip helper for software deployment over more than one router, Ip helper form a unicast from the broadcast..

just to update

Good luck


New Member

Wake On Lan Questions

True that`s i`m was confused cauz ip help will tranlsate broacast request to unicast from Client to Server but WOL i figure out it`s a Server to Client interaction


Wake On Lan Questions

shame on me

you're right

wait for your tests and posts.

Hall of Fame Super Silver

Wake On Lan Questions

I have implemented WOL for a customer and found that ip helper is indeed required. The WOL server sends out the packet to activate clients. This works well and requires no network help if the server and client are in the same broadcast domain (in the same subnet). But when the client is one or more hops away then some network help is required.

ip helper-address does forward broadcasts. But your assumption that helper-address turns the broadcast into unicast is not necessarily correct.. If I configure ip helper-address (where is a /24 subnet) then helper-address is sending a directed broadcast. And if the gateway on 172.16.100 has enabled directed broadcast then the WOL packet will be broadcast onto that subnet.

For a good while Cisco IOS has disabled directed broadcast. So on the receiving router interface you need to enable directed broadcast.

If you configure ip helper-address on the router interface of the subnet where the server is located and if you configured ip directed-broadcast on the router interface where the clients are located then WOL should work.



New Member

Wake On Lan Questions

Hi Rick

I was able to make it work today without the ip helper , all i did was enabling direct broadcast on my SVI where the clients sits and use an ACL to restrict the Direct broadcast message

Thanks for the help guys