L2 loop protection on a not mananaged switch.

RouterOS General
1

Hello , guys , as tittle says, I need to protect my network against L2 loops produced by an unmanaged switch.

The loop occurs when some one connects tho ports of same switch with a cable (see picture bellow).
I would like to be able to shutdown the port of my managed mikrotik when the loop occurs.
I have been testing with stp running on my managed switch but have no luck so far.
Edge port feature would help ?
It is very critical situation, since when loop ocurs I have a broadcast and arp storm flooding my network, and also have many mac address flapping on upstream switches.
I know I can limit broadcast storm but I would like to shutdown the port.
Take a look bellow:
external_protection_mini.png

2

on a CRS switch can be implemented, but on integrated switch on RB751 or rb951 dont know how to do it or if can be

3

Chechito , i dont understand your comment, could you be more clear?
Witch feature are you refering at?
Do you think is there any especific mechanism to handle my problem ?
Thanks for your response.
Leandro.

4

loop protection can be implemented on mikrotik CRS switches using inbound broadcast limit rate and drop dynamic move on ports.

on integrated switches on little mikotiks i dont see that features

5

Very strange … I performed same test replacing mikrotik for another switch witch rstp feature and it worked as espected, it takes half second to detect the loop condition and move the port to “bloqued” state.
I think that switch notice the loop condition when he receives a bpdu over the same port it was sended.
I can not get same result with my mikrotik yet.

6

maybe using static host mapping on switch can help a little to mitigate the situation preventing the mac flapping on mikrotik fsb poisoning and amplifying the storm.