Catalyst 3560 - Windows Deployment Services - IP adress Problem

[Andreas.Lechner]

Hello

i'm using some catalysts 3560 with 10 VLANs and inter vlan routing.

we use a windows deployment services server to install our workstations.

the pxe boot works fine. the image is loading, and when the windows 7 PE is booting, the dhcp request failes.

when i use a small not manageable switch between the computers and the catalysts, it works fine.

all other things work fine.

do you have any ideas?

best regards

Andreas

[darren.g]

Andreas Lechner wrote:
Hello 
i'm using some catalysts 3560 with 10 VLANs and inter vlan routing. 
we use a windows deployment services server to install our workstations. 
the pxe boot works fine. the image is loading, and when the windows 7 PE is booting, the dhcp request failes. 
when i use a small not manageable switch between the computers and the catalysts, it works fine. 
all other things work fine.
do you have any ideas?
best regards 
Andreas

Do you have an ip helper defined on the segment which is causing the problem? Especially if your DHCP server is on a different segment to the one the windows 7 PE box is on?

Cheers.

[Andreas.Lechner]

Hi,

yes the ip helper works fine.

dhcp also works fine in this network on all win xp and win 7 clients.

at the pxe boot the pc gets an ip adress, is loading the windows PE and in the windows PE it didnt get an ip adress when the pc is directly connected to the catalyst.

when we use a small noname switch between the pc and the cisco it works fine.

best regards

Andreas

[glen.grant]

  Do all your user ports have spanning tree portfast enabled on the ports ?

[Andreas.Lechner]

yes portfast is enabled on all access ports

[darren.g]

Andreas Lechner wrote:
yes portfast is enabled on all access ports 

I've done a bit of looking around, and this could be caused by a couple of things.

On the switchports you're plugging your PXE build nodes into, add the following command

switchport nonegotiate

and see if that helps.

if that doesn't work, look for the keyword "ip broadcast address XXXX" on your SVI or routing interface - if it's there, remove it with the "no ip broadcast address" command and see if that helps.

There's a Microsoft KB article which kinda supports the latter located here

http://support.microsoft.com/kb/928233

The first solution is more likely, as the "switchport nonegotiate" disables 802.1x negotiations on the port, which seems to be the bit which breaks the PE DHCP requests.

Oh, and make sure you explicitely specify the "switchport mode access" component in your port configuration.

Cheers.

[Andreas.Lechner]

hmm, switchport noneogtiate doenst help

i will search for the broadcast adress and post the results here

[darren.g]

Andreas Lechner wrote:
hmm, switchport noneogtiate doenst help 
i will search for the broadcast adress and post the results here 

Well, now I'm stumped. Sorry. :-(

[Matt Duncan]

I am running into a very similar issue...did you ever find a fix?

[Andreas.Lechner]

hi matt,

maybe, the PCs are connected over a cat 7 Cable with tera/rj45 patch cables.

When the PCs are directly connected to the switch over a normal Cable (both sides rj45) it works fine.

we think that we have a problem with the cables.

Now we are waiting for new tera/rj45 cables

best regards

Andreas