We had a known cisco software bug on 3750 switch where if you enable DHCP ping check before it gives out address it causes chaos if more than 50 devices ask for DHCP at once.
workaround is to disable the ping check - Done this.
Ok, but now, in the event of switch failure/reboot the DHCp will allocate addresses from the beginning of the range again, potentially causing a DHCP conflict.
I have heard there is the function to enable the switch(DHCP server) to write a bindings list to a TFTP server periodically, and in the event of a switch reboot, it checks for the binding list on start up before issuing any DHCP addresses.
How do I acvieve this?