@Inf1nf1ty33 

The UG for this switch. https://static.tp-link.com/2020/202011/20201103/1910012903_T16_T26_UG.pdf

Do you mean based on the Port and MAC you define the DHCP/IP? Could you explain this by examples? How can you block another DHCP server? The DHCP server is not created on the switch? 

@John1234 

Thx for your reply, I have already studied the User Manual and tried different things, but I was not able to block the DHCP with DHCP snooping.

For your understanding. 

I have connected two different networks :

192.168.1.x

192.168.4.x

Subnetmask on Both Networks are 255.255.248.0 so the Clients can communicate with each other.

There are also two Routers (192.168.1.254 and 192.168.4.254) which are acting as DHCP Servers.

There are also one internet connections per each router.

So the Clients on the 192.168.4.x subnet should not DHCP adresses from the router with the IP 192.168.1.254 and vice versa.

On D-Link Switches there is an Option to just allow a specific port acting as DHCP Server and as an extra option to allow IP's from the DHCP Server.

I have solved this in the meantime with blocking the router with an ACL on the TP-Link switch, but it would also be interesting for me how DHCP Snooping is working.

As i understood this could block DHCP traffic from the second firewall.

I have tried different options but had no luck.

Thx