Switch stacking

RouterOS General
1

I tried to use search with some non conclusive results… the most closest is post from 2021 that mikrotik does not support stacking and the closest to that is some magic that is not the most reliable…

So anything changed ?
Does mikrotik support stacking ?

I want to have 2 switches in the stack (stack-switch01, that composes of switch01-1 and switch01-2). the first sfp of both ports will go to the remote switch 02 , and second sfp port on both switch will go to the switch03

stack-switch01
I_ switch01-1-------sfp01-------switch02 (sfp01)
I -------sfp02-------switch03 (sfp01)
I_ switch01-2-------sfp01-------switch02 (sfp02)
-------sfp02-------switch03 (sfp02)

  • do hope formating is not going to break that much. the switch02 and 03 are not stacked.

Is there a way to achiev this on mikrotik and with the same functionality like cisco stack + lacp ?

edit: i m not mentioning here stack port (i dunno for example sfp03 and sfp04…not central to the question)
Thank you.

2

hello,

have you read this wiki?
maybe it can help you.

https://wiki.mikrotik.com/wiki/Manual:CRS1xx/2xx_series_switches_examples

3

AFAIK the closest thing to stacking, supported by Mikrotik (ROS in particular), is port extender. IMO it’s pretty poor approximation, but I guess there are use cases for port extender as well.

4

yeah, that was the magic i saw in some post… nope , this wont gonna do.
So no for stacking. Well i ve tried.

Thank you for the help.

5

It’s arguably better than stacking, when used correctly. Look at Cisco Nexus port extenders and Catalyst 6800 Instant Access switches, for instance. Can make your entire infra look like a single switch, which most stacking inplementations cannot do due to distance limitations.

6

Well, distance between CB/PE can indeed be much longer. But that’s about the only thing better than in traditional stacking. Stacking interface is one thing, switching performance is another thing. Both really suck in CB/PE setup because all switching is performed by CB (even if communicating devices are both connected to the same PE) which both overloads CB switching engine and interconnect links. Not to mention that stacking interfaces are usually faster than fastest of the rest of interfaces.

7

Not trying to resurrect an old thread, but this is the top result in Google, so I wanted to surface this for folks looking in the future:

CRS3xx, CRS5xx series switches, and CCR2116, CCR2216 devices are all capable of MC-LAG (Multi-Chassis Link Aggregation Group), which is almost stacking. (Distributed switching, but also distributed configuration planes.)

https://help.mikrotik.com/docs/spaces/ROS/pages/67633179/Multi-chassis+Link+Aggregation+Group

1 Like
8

MLAG is a very different thing than stacking. For one, it requires end devices to use LAGs towards the "stack". Another one: MLAG peer link can become a serious bottlebeck for similar reasons as for CB/PE links. And not to mention single control plane of proper stacks.

So no, MLAG is not almost stacking.

9

this is actually the closest to the "stack" that mikrotik has ever gotten and quite usable for my use case
THANK YOU for bringing this up

10

i wonder if they can support mclag with 3 or 4 switches...

11

Fair, I should have said kinda stacking.

At the end of the day: It all comes down to why you were staking in the first place, and I'd argue that MC-LAG handles quite a few of those use cases.

If I'm not mistaken: Non-LAG interfaces will still populate the ARP table and allow traffic to flow between peers via the peer-port, provided VLAN memberships are correct. Even a stack will have chassis-to-chassis bandwidth constraints to consider, but MC-LAG can use a bonded link between peers, so you can somewhat mitigate bottlenecks there too.

It would be neat if Mikrotik had a CRS with a bunch of SFP+ alongside 2 or 4 40+ Gbps links for doing this very sort of setup.