We have two vlans. VLAN10 - 192.168.0.0/24 and VLAN 11 - 192.168.11.0/24. Using IP helper-address, we have one dhcp server sitting on VLAN 10 and it works find when you plug a new computer into any network. The problem occurs when we move one machine from one vlan to the other. iIt apears that he machine that got 192.168.0.111 for instance from vlan 10 still tries to get the same ip from VLN 11, which results in freeze-up.
the workaround we've found so far is the following. we issue ipconfig /release before we move a computer, remove that ip from the dhcp server and move the computer to a differnet vlan, which is very very cumbersom and we look stupid. please help!!
Are the two DHCP scopes in the same DHCP Superscope? If they are you need to split them into two separate SDHCP scopes. Superscopes are not for simplifying the configuration of the DHCP server they group together IP networks that share the same broadcast domain - i.e. secondary addressing. I have seen this many times and the cause is always the same - DHCP Superscopes.