Hello, I'm new to Mikrotik and I recently purchased 3x HAP AX3s specifically for EVPN support. I come from using VYOS and I'm a network engineer as my day job. I'm due for a wireless upgrade at home and Mikrotik has really caught my eye with the new features that are being worked on in RouterOS. I really like that these APs are also full blown routers, super powerful and customizable.
I have built an OSPF + eBGP EVPN + VXLAN fabric using 2x VYOS Spines and 3x HAP AX3s as leafs.
EVPN has been working when testing wired ethernet. Ethernet interface down state withdraws MAC routes as expected. I can unplug my PC from AP1 and go to AP2 no issues while being wired, MACs get withdrawn and advertised. However, when bridging WiFi and testing wireless client roaming between APs, I ran into MAC mobility problems.
For example, my phone connects to AP1 and then roams to AP2. AP1 still has my phone's MAC in the EVPN table and does not withdraw it. This prevents communication as return traffic is getting sent to AP1 and not AP2.
Other vendors have solved this problem by using EVPN MAC sequencing. This allows all VTEPs to understand who has the latest route and any stale / older routes can be withdrawn from originating VTEPs. This is very important for VMs, vMotion, client roaming and otherwise dynamic environments.
VYOS and FRR support MAC moves/mobility. This is the last piece of the puzzle for my network to function properly. When will MAC moves be supported? I think I'm planning to build a flood based network for the time being while I wait for the fix.
In addition, 7.20rc1 has some bugs with BGP where after some time, exporting the configuration hangs up and times out. Eventually the routing table stops updating as well and CPU spikes to around 70%. A reboot typically fixes any of these issues. These issues might have stemmed from misconfiguration as I have gotten more stability as I have finalized my design and configuration based on other vendor's standards.
I'm on the edge of wanting to order some CCRs for my rack and network core. Would love to hear the timeline for more EVPN support! Thank you for reading!
Arista EVPN Mac Mobility:
A common scenario in a data center environment is Virtual Machines (VMs) moving between physical servers, for maintenance or performance reasons. This will result in the MAC of the VM being learned and advertised by a new VTEP.
To cater to this situation, a sequence number is attached to the new MAC advertisement, ensuring an EVI wide refresh of the MAC table, with VTEPs updating their forwarding tables to point to the advertising VTEP as the new next-hop for MAC address.
When a MAC address is learned and advertised for the first time, it is advertised without a sequence number and the receiving VTEP assume the sequence to be zero. On detection of a MAC move, such as a MAC is learned locally when the same MAC route is active via a type-2 advertisement, then the sequence number is incremented by one, and the MAC route is advertised to the remote peers. The original advertising VTEP, receives the MAC route with a now higher sequence number and withdraws its own local MAC route. All other VTEPs flush the original MAC route, and update their tables with the new higher sequence number route.