RB2011 Problem bridging WAN1 to other port

Hi,

We have old old x86 Mikrotik with 3.30 firmware.

On this PC we have 4 ports.

Port 1 - WAN1 (On WAN1 we have 254 public addresses each added in IP>addresses)
Port 2 -WAN2
Port 3- Connected to small switch for public addresses
Port 4 - Trunk and all Vlans

Port 1 and Port 3 are in bridge1

So I can connect my laptop to this small switch (connected to port3 in MT) and get any Public address that I want.

It was working fine for 5 years.

Today our new RB2011 arrived. We wanted to replace this x86 Mikrotik with new RB. So I just coppied most of configuration from x86 to new RB.

I wanted to test everything so while old MT was still working I connected ETH1 from new RB(which is WAN1) to this small switch and configured Public Ip address. It was working fine until I added WAN1 and ETH3 on new RB to bridge.

Now ALL my network stopped working on new RB and old MT.

After many hours I tried setting ETH1 as master port for ETH3. It started to work just fine. But I am just curious. Why can’t I add WAN1 and other port to bridge? It ruins all network. On 3.30 it was working fine. On 6.18 it doesn’t work. And it even breaks running x86.

Are you running NAT on the RB2011?

Could it be CPU maxing out on the RB2011? Bridging will use CPU.

No, it’s impossible.

CPU can’t get that high with simple Bridge of wan and empty port.