Core and data center applications are the strengths of Arista products. The distribution layer is also a good fit. For the access layer, it would be more of a niche product.
MikroTik Cloud Router Switch work very well as layer2/3 switches in enterprise environments, aggregation or distribution layers. Example: in our case (ISP) we use CRS326 and CRS317 at multi-dwelling units to finish the customer lines, manage vlans of service and apply basic qos. They offer a good variety of ports 1/10G, which is perfect for connecting other ISPs or connecting corporate end users. MikroTik Cloud Router Switch would work fine in low-traffic Routing and Switching, you could configure L3 Hardware offloading and serve some significant traffic, but you may missing some features like, mangle, nat, firewall or other things that may be solved with other device in an upper layer of infrastructure. Based on our experience MikroTik Cloud Router Switch is not good for high performance traffic, they are not optimized for heavy L3 routing task. Example: if you use a CRS as core or router in a small DC or IX the result is traduced on high cpu usage and load performance. If you are looking for special works, MikroTik Cloud Router Switch in this aspect is out.
Powerful features at a low price: MikroTik Cloud Router Switch provides a good variety of features that are not present on more expensive brands. Flexible deployment options: SwOS for simple switching use cases and RouterOS for more advanced configurations. Winbox is a fast and responsive tool for configuring, maintain and monitoring the traffic or other variable. Why it doesn't score higher, we think that the learning curve for new users could be hard. Sometimes the logic configuration can be unintuitive example: bridge filtering, vlan interfaces. Inconsistent UX Across RouterOS versions, some features may change without clear documentation causing confusion missconfig or incompatibility between versions. Documentation and support are poor, official documentation is fragmented and depht in some cases, the active community should be your best friend.
I have used the Catalyst 6500 series in the past. From my point of view, the Arista surpasses the Catalyst on just about every front. Originally we were planning on implementing the Nexus 7000/7700 series switches for our core. Though a little more feature rich, it did not provide features we needed that the Arista did. The Nexus also was a confusing and complex platform to work with. Also, the Nexus was a significantly more expensive solution. Although very happy with the Arista switches we may evaluate the Aruba HPE 8400 chassis-based switches along with Arista switches in the future.
We chose MikroTik Cloud Router Switch because it met our technical requirements without significantly affecting our budget. MikroTik Cloud Router Switch offers a performance reliable and scalable for access and aggregation roles and is easy to integrate with our existing infrastructure (Mikrotik CCR). While it doesn't offer enterprise-class UX, or automation frameworks out the box, its disruptive focus, control and granular configuration convert it in an attractive option for ISP operations.
