[PC1]---lan----[RT1 / DHCP relay / DNAT]---wan---[DHCP server] [PC2]---------/ / [PC3]----------/
- DHCP relay makes the a DHCP broadcast into a unicast and
- Forwards it to the DHCP server which
- Then responds and sends a DHCP reply which
- Reaches PC1.
However PC1 saves the DHCP server information in it's network config. Then, when half-lease time has come, it requests a new address using unicast directly from the DHCP server.
Problem: The source IP is the PC1 IP (no source nat). So the DHCP server sets the destination IP as the IP of PC1 - which gets dropped on the router.
Question: What is the common solution to this problem? Source NAT configuration? What are some other ways to solve it?