vlan question

RouterOS General
1

Hello,

We have routerboard with
ether2 and ether3 - in bridge1
ether4 and ether5 - in bridge2
now we need special port ether6 which should be a member of both bridges, but in bridge1 as untagged default vlan (vlan1), and in bridge2 as tagged vlan2.
This is can be done very simply on a managed switch, but how to do it on Mikrotik Routerboard?

2

Hey

A Tik much more than managed switch :wink:

To do that:

  • merge both bridges
  • use vlans to separate current logic bridges
  • use these vlans as tagged / untagged on eth6

eth2 & 3 would become vlan x
eth4 & 5 would become vlan y

vlan x would be untagged on eth2, 3 & 6
vlan y would be untagged on eth4 & 5, and tagged on eth6

Combination of example1 & 2 @https://wiki.mikrotik.com/wiki/Manual:Interface/Bridge#VLAN_Example_.232_.28Trunk_and_Hybrid_Ports.29

3

I can not merge bridges, because bridges have different ip-addresses and dhcp-servers on them.

4

Hi,

yes you can.

Merge bridges, add appropriate VLAN interfaces, so CPU has access to VLANs and then move your DHCP servers and IP adresse to those VLAN interfaces.What you want to do is doable with one bridge an VLANs.

Regards,
Ape

5

but I don’t want to create additional vlan interfaces

6

why not?

7

GUI of managed switch creates VLANs internally and hides it from you. On mikrotik you just have to do it yourself. Something like this:

/interface bridge vlan filtering=yes
add name=bridge
/interface bridge port
add bridge=bridge frame-types=admit-only-untagged-and-priority-tagged ingress-filtering=yes interface=ether2 pvid=100
add bridge=bridge frame-types=admit-only-untagged-and-priority-tagged ingress-filtering=yes interface=ether3 pvid=100
add bridge=bridge frame-types=admit-only-untagged-and-priority-tagged ingress-filtering=yes interface=ether4 pvid=200
add bridge=bridge frame-types=admit-only-untagged-and-priority-tagged ingress-filtering=yes interface=ether5 pvid=200
add bridge=bridge ingress-filtering=yes interface=ether6 pvid=100  # frame-types=admit-all is default
/interface bridge vlan
add bridge=bridge untagged=ether2,ether3,ether6 vlan-ids=100
add bridge=bridge tagged=ether6 untagged=ether4,ether5 vlan-ids=200

Of course there’s more to it (how other ports should behave, how’s management of RB itself done, does RB device interact with any of those groups of ports, …), but this code above illustrates requirements as set forward in original post.