DHCP Problem

[liamwalk]

Hi,

We have just encountered a DHCP problem involving clients attached to Cat4006 access layer switches. The distribution layer is Cat6509.

Clients on one particular VLAN suddenly cannot obtain DHCP address. Static client cannot ping virtual HSRP default gateway address, but can ping out past it!! Trace on VLAN when performing DHCP request shows only DHCPDISCOVER packets arriving at VLAN interface on distribution MSFC......the packets are not being forwarded using IP Helper address to third party DHCP service provider. All other VLANs work OK.

Software versions are:

Cat4006 7.3(2)

Cat6509 7.3(2)

MSFC 12.1(11b)E4

Does anyone have any ideas???

[umedryk]

I guess this has probably to do something with the change in subnet mask one of the clients, not necessarily in the problematic subnet.