Mirroring ports on Mikrotik

Most Mikrotik routers have switch chips. On most models you can use the switch chip to mirror a port to another port on the same switch chip. On the RB1100AHx2 there are two Atheros 8327 switch chips. One is ports eth1-eth5 and the other is eth6-eth10.

Mikrotik has a wiki page on what models have which switch chip, and what is supported.

To mirror all eth1 to eth2 traffic from the CLI:

[admin@Mikrotik] /interface ethernet switch> print

Flags: I - invalid 

 #   NAME      TYPE          MIRROR-SOURCE    MIRROR-TARGET    SWITCH-ALL-PORTS

 0   switch2   Atheros-8327  none             none            

 1   switch1   Atheros-8327  none             none            

[admin@Mikrotik] /interface ethernet switch> set mirror-source=ether1 mirror-target=ether2 0

[admin@Mikrotik] /interface ethernet switch> print

Flags: I - invalid 

 #   NAME               TYPE          MIRROR-SOURCE              MIRROR-TARGET              SWITCH-ALL-PORTS

 0   switch2            Atheros-8327  ether1                     ether2                    

 1   switch1            Atheros-8327  none                       none                      

[admin@Mikrotik] /interface ethernet switch> 

Or from WinBox, from the "Switch" menu: