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DHCP assigning improper addresses for the VLAN

HP procurve 5406 at the core and HP 2848 at the edge, clients are all WinXP SP3, PXE clients are Altiris Deployment server clients

I wouldn't believe it if had not seen it with my own eyes. A recent rash of clients not getting DHCP addresses in a timely manner had me looking at one users PC. This PC is attached to a switch which is the 103 vlan, but it gets and an address from the 102 vlan! This is in both windows and PXE. Once I network boot and have Win PE loaded, DHCP fails to get an address.

I checked some more machines on the 103 vlan and on some I saw it get a vlan 102 address in PXE and then get a 103 vlan address in Windows.

In other instances I saw machines on the 103 vlan get vlan 102 addresses in PXE and fail to get addresses in windows. Upon trying ipconfig /renew on these same machines, I would receive an access denied error.

Last time I saw the access denied message, related to dhcp, I had a broadcast storm caused by someone connecting two ethernet ports in the same room.

Sort of scketchy details, but maybe someone out there has seen a similar scenario. The other vlans on the network are all working fine all the problems are on 102. I'm pretty sure I have something plugged in somewhere it shouldn't be, but have yet to find it.
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rmstewart70
Asked:
rmstewart70
3 Solutions
 
gheistCommented:
are you sure cabling is correct?
no leaks between subnets? (disable HP routing accelerator to make sure)
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nociSoftware EngineerCommented:
The broadcast storm should not have happened if you had spanning tree enabled.

First check that no one created a link between the 102/103 network using a patch cable or because the seperation is then lost.
For HDCP at fist only Broadcasts are used..., and the first responding DHCP servers gets used...
Check mac addresses in the mac table and see if vlan 102 macaddresses are visible in the vlan103, if so then there also is a port mentioned where it should be forwarded to...
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jimsoyaCommented:
After hours, you can disconnect or disable uplinks from individual wiring closets while testing CHCP to see which closet may have the cabling error.
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