Hi!

We need to find a way to connect to a Cisco VSS LACP link with two routers.

Our customer uses two Cisco Catalyst 4500-X with VSS. We are connected with two 10G fiber links (one from each 4500-X). These links are connected to one of our routers to a LACP bond.
Routing to and from our customer is static. We run BGP in our network.

After a hw failure of this router, the customer requests a redundant setup, but they don’t want to switch to BGP ECMP.

Which means we need to connect this LACP bond from the Ciscos to two routers.
As far as I know RouterOS doesn’t support MLAG or how the other vendors call it.

What options do we have?

What options do we have?

Getting other vendors hardware.

Eg. Cheapish Cisco Nexus 3064 Switches, which nearly support anything you might want to configure

A port channel from a VSS pair can only go to a single device, or a pair of devices pretending to be one (eg Nexus VPC, or Catalyst stack). It can't go to two different devices because on a frame by frame basis either link could be used. How are these two WAN routers going to be configured, will they have separate WAN links as well? And if let's say WAN A fails then will traffic to router A be forwarded to Router B and on to WAN B?

Depending on the details I would be inclined to use L3 connections to the two routers. With equal costs these could load share on a connection by connection basis. And use an internal routing protocol to learn and fail over. Alternatively run a L2 connection to each router and configure IP SLA and Object Tracking to test each path. Again these could be equal cost load sharing. You don't need to worry about the path back to the VSS as that's a single logical system, it won't matter which physical switch data is sent to.

Regarding the Nexus 3K, maybe. Remember to cost in Enterprise LAN licence, or equivalent. to get full routing features.

Why not build LACP channels from the 4500X to two different MikroTiks and connnect the MikroTik routers together via BGP?

What role do the MikroTik routers and 4500X play in this network? what are their jobs?