Need to Setup Failover

RouterOS General
1

I have CCR 1036-8G-2S+ Router and 24 port unmanaged D-link switch. The internet is configured and working fine. The problem is i need to deliver a fiber and rf line to a customer in bridge mode.
I take two output from 24 port unmanaged D-link switch and deliver it to customer through one fiber and one rf line.
There is a mikrotik RB750r2 router at customer end. Need to know how to setup failover in bridge mode setup.
Note: The customer need to connect one output from the RB750r2 and assign it to their firewall. At the time one input from our end need to work.

Please help with this issue.

2

Bridge mode, redundancy, and unmanaged switch are not a nice combination of requirements, as even in the unlikely case that the unmanaged switch supported RSTP, you wouldn’t be able to set up the priority of the paths on it (leaving aside that redundancy was not the primary design goal of STP). So you need something that will make the two paths distinguishable from each other at the RB750r2 end, meaning that the two uplink ports must not be directly bridged together there. To me, the simplest solution seems to be to misuse VLANs for this purpose:

 _______________________________________                                       ________________________________
|          .--[U vlan-if-A T]==..       |       ________                      |                         RB 750 |     _________________
|         /                     \\      |      |        |======[ fiber ]======|=[T vlan-if-A U]----.           |    |                 |
| ---[bridge2]    CRS 1036    [bridge1]=|======| D-link |                     |                  [bridge3]-----|----| customer's gear |
|         \                     //      |      |________|======( radio )======|=[T vlan-if-B U]----'           |    |_________________|
|__________'--[U vlan-if-B T]==''_______|                                     |________________________________|


U: untagged end of /interface/vlan
T: tagged end of /interface/vlan
--- untagged traffic
=== tagged traffic

RSTP configuration on bridge2 and bridge3 would then take care about priortity of the fiber link over the radio one.

But there may be some additional requirements that make this approach impossible - bridge1 is the current bridge to which the unmanaged switch is connected, so if you need the customer’s end to be a remote part of this bridge, you would bump into issues with MTU etc., leaving aside STP. So you have to provide more information if this inspiration is not sufficient.

In such case, you would have to use a single EoIP tunnel with a manually configured MTU, or maybe an L2TP one in BCP mode with MLPPP enabled, instead of the two pairs of VLAN interfaces, and handle the failover at L3 level (transport packets of the tunnels), as that way it would be possible to overcome the issues with STP and MTU while making the L2 tunnel a member port of bridge1 at the CRS 1036 end.

3

If fiber is directly connected to 750 G then this could be an option. configure bonding on 750, with active backup mode. once the fiber goes down traffic shfts to wireless by itself.