how to control rancher dhcp assign ip address?

I don’t known how rancher dhcp assign ip mechanism and which module responsible this, how can I control dhcp IP assign one by one?
I have a scenes:
start a A container with ip address:10 mac address:a, B container with ip address:11 mac address:b, C container with ip address:12 mac address:c,
when I delete container A, then add container D.I don’t know which IP address and mac address should D use, I don’t know how rancher assign IP address to D?
If D with IP address 10, then mac address D, the switch of arp table still record IP:10,mac:a, then the network packet to container D can’t reach D container, the network is
unreachable. How can I resolve this problem in this scenes, how can rancher assign IP one by one, util ip address 10 entry in arp table is expried