need test

You may get significantly faster packet processing and lower CPU utilization by removing ports from a bridge, where possible, to add them to a switch group.

When router ports are bridged, all packets going through these interface are processed using the router's CPU. However, if the ports are in the same switch group, the special switch chip processes those packets, decreasing load on CPU.

So, in the case of an RB2011 with two switches and ten Ethernet ports, you could:

• make ether1-gateway the Internet (WAN) gateway
• make ether2-master to be a 'master' port for ether3 through ether5
• make ether6-master the master for ether7 through ether10

Don't forget that before assigning master port you must remove them from any bridge.

/interface
  set ether1 name=ether1-gateway
  set ether2 name=ether2-master
  set ether3 name=ether3-slave
  set ether4 name=ether4-slave
  set ether5 name=ether5-slave
  set ether6 name=ether6-master
  set ether7 name=ether7-slave
  set ether8 name=ether8-slave
  set ether9 name=ether9-slave
  set ether10 name=ether10-slave

/interface ethernet
  set ether1 master-port=none
  set ether2 master-port=none
  set ether3 master-port=ether2
  set ether4 master-port=ether2
  set ether5 master-port=ether2
  set ether6 master-port=none
  set ether7 master-port=ether6
  set ether8 master-port=ether6
  set ether9 master-port=ether6
  set ether10 master-port=ether6

After doing that you'll have a WAN (gateway) port plus two separate and independent switch groups. Assuming you want them to be connected (LAN bridge), there are two options:

1. Use a software bridge
   • Perhaps sfp1 + ether2-master + ether6-master
2. Connect them using a cable
   • Wastes physical ports

In this case, traffic between switch groups switch1 and switch2 will be processed using the CPU, so any packet going from any interface in group 1 to group 2, or vice versa, will be processed using CPU.

/interface bridge
  add name=bridge-local
  port add interface=ether2 bridge=bridge-local
  port add interface=ether6 bridge=bridge-local
  port add interface=sfp1 bridge=bridge-local

/ip address add interface=bridge-local address=192.168.1.1/24
/ip dhcp-server add interface=bridge-local address-poll=[name of your address pool]

Just connect any port from group 1 (ether1-5) to any port in group 2 (ether6-10). Yes, it takes 2 port and only applicable if you have ones. If all ports in one of the switch groups are already in use, I'd suggest using first option (bridging).