How to get IP from ISP via dhcp on port 3?

Question

Computer networks

There is a mikrotik 750up in the first port, a cable from an ISP is plugged in, which distributes white ip via dhcp. The second port is the local network 192.168.88.0/24. Internet running masquerading is configured. Tell me what manipulations need to be done so that when devices are connected to the third port, a white operator ip is issued.

Answer 1

Merge ports eth1 and eth3 into a bridge.

Answer 2

NAT+Masquerading and bridge on the right ports.

Answer 3

In your case, it will not work to get 2 IPs via DHCP from the provider on 1 microtic connected via 1 wire - there will be a conflict of mac addresses. You need to put any simple switch in front of Mikrotik, with one port to the provider, and two other ports to Mikrotik, and on each port for a separate dhcp client, the main thing is that the ports are not in the same bridge or with a common master port, otherwise you will catch loopback.
Well, or agree with the provider to connect you with a trunk (vlan 802.1q).

Answer 4

Create a bridge ---> reconnect ether1 and ether2 ---> bridge ports. then in /ip dhcp-client add interface="ether3" ......... and that's all