Network Boot DHCP/WDS

[SteveBentley]

I've got a WDS server set up, authorised as a DHCP server, and its IP set as a helper in the "real" DHCP server.

 

I'm finding that all but half a dozen of the machines in one of our labs are failing to pick up DHCP under network boot (but the DHCP client in Windows works fine). These half dozen machines are connected to a workgroup hub rather than directly to the switch.

 

Am I missing something here?

 

cheers

 

Steve

[pete]

If the switch is intelligent / managed, have you told it there's a hub plugged into that port? You might need to turn on portfast / modify the spanning tree config on that port.

[SteveBentley]

The machines which are connected via the hub work.

 

I've tried disconnecting the hub but that doesn't bring the other machines back to life.

[SYNACK]

Sounds like it could be spanning tree protocol interfearing on the managed switch ports by isolating the hosts for its set time period to make sure that they are not loopbacks. This delay on ip connectivity probably just long enough to deprive the PXE boot portion of the boot process of ip connectivity. As the hub is already plugged in and live it has already gone through the isolation period and so anything plugged in to it is live from the start.

 

You may need to put the switch into portfast STP mode to allow the clients access at the start of the boot process.

[SteveBentley]

Thanks for the help guys, our network guru has turned on portfast and it's working perfectly.