Hi all! New to RouterOS/Mikrotik and purchased a RB1100 AHx2. I was using a managed switch, so replacing it by a router introduces a lot of new concepts to me. I've been reading a little, and some questions came to my mind.

My scenario: Internal LAN with more than 5 ports needed, and WAN port for Internet access.

From what I've been reading -> Switch 1: Ports 1-5, Switch 2: Ports 6-10 -> 1-5 and 6-10 can be linked by physical bridge.
If I want more than 5 ports I need to create a bridge between 2 of the ports, but this is CPU load as it will be software bridge.

Q1: In order to do the physical bridge, I can go to Interfaces and set one of the ports in every switch as master (e.g: ports 1 and 6), and the rest as slaves (2-5 to 1, 7-10 to 6). But I've seen that under the "switch" configuration option for both switched, I can check the "switch all ports" option. What would be the difference between using this option and doing it through the interfaces menu?

Q2: I've seen that in the "switch ports" menu, port 11 appears as belonging to switch 1 and port 12 to switch 2. They are named as "Switch 1 CPU" and "Switch 2 CPU". Atheros 8316 has 5 ports, so I assume this ports are not part of the switch... how are they related to both switches? What is the meaning of "Switch CPU"?

Q3: In my scenario, I think the best option is connecting WAN on port 11,12 or 13. For the LAN part, I can either software bridge the 2 switches to make it behave like one, either make 2 internal subnetworks on my LAN to avoid software bridging (but then I would need routing between the 2 switched, so I don't think I would be getting benefits in terms of cpu of avoid software bridging).
What do you think of it?

Thanks in advance!

Cheers

1. See the description of switch-all-ports at: http://wiki.mikrotik.com/wiki/Manual:Sw ... p_Features

2. The Switch CPU ports affect what traffic (e.g. which VLANs) are seen by the CPU. In effect the switches have 5 external ports plus the "port" that the CPU sees.

3. Ether 11 has a direct CPU path which will often make it a good WAN candidate.

Thanks for the reply Celticomms.

1. I had seen the description, only hadn't notice it was referring to Atheros 8316. I mean, in the RB450G it made more sense to me as you have only 5 ports, so you can choose if you want to use one for WAN or not for instance.

To summarize: YES-> ports 1 and port 6 will act as a regular port switch; NO -> ports 1 and port 6 will act as separate ethernet ports (but also will ports 2-5 and 7-10 unless they are configured as master-slave ports on the interface menu, right?)

2. Does this mean also that each separate is somehow linked to one of the cpu cores? (Trying to get why port 11 is linked to switch1 and port 12 to switch 2)

Thanks!

Have a look at this diagram:

http://i.mt.lv/routerboard/files/Block-RB1100AHx2.pdf

Thanks,

From this diagram and under my understanding:

1. yes
2. No, no related to core. But still can't tell from it what makes that 11 is related to switch1 and 12 to switch2.

But still can't tell from it what makes that 11 is related to switch1 and 12 to switch2.

What makes you think that they are?

The default config for my Switch shows switch1 cpu and switch 2 cpu.


I was assuming these were ports 11 and 12 as I had ether1 to ether10, but now that I am rethinking maybe this "switch 1 cpu" and "switch 2 cpu" are not related to port11 or port12, they are just "logical".

maybe this "switch 1 cpu" and "switch 2 cpu" are not related to port11 or port12, they are just "logical".

Correct in the sense that they are not available externally. They represent the path between the switch chip and the CPU which is of course a physical path internally. Using those ports you can control which traffic is presented to RouterOS.