Distributed virtual routers have a positive impact on the network architecture as a whole by avoiding bottlenecks and single points of failure seen in the legacy model. Both east/west and north/south traffic can be routed and forwarded between compute nodes, resulting in a more efficient and resilient network. SNAT traffic is limited to a centralized node, but highly-available SNAT routers are currently available in an experimental status and will be production-ready in future releases of OpenStack.
While distributed virtual routers help provide parity with nova-network's multi-host capabilities, they are operationally complex and considerably more difficult to troubleshoot if things go wrong when compared to a standalone or highly-available router.
In the next chapter, we will look at the advanced networking service known as load balancing as-a-service, or LBaaS...