Amazon EC2 Deployment Options
Romana is network agnostic and supports a wide range deployment options including:
- Flat and segmented layer 2 networks
- Layer 2 virtual networks
- Layer 3 CLOS/Spine-leaf networks
- Routing on the host (RoH) network configurations
- Amazon VPCs
Amazon EC2 is one of the most popular platforms for running Kubernetes, but when it comes to networking, EC2 has some limitations that make deploying production clusters unnecessarily complex and unable to operate with peak performance.
Romana lets users avoid these limitations and deploy production clusters across availability zones without an overlay and deliver native VPC network performance at any scale.
Single Availability Zone Deployment
Kubernetes pods on instances running in a single VPC Availability Zone use routes installed by Romana to reach all pods. No VPC routes are necessary. Routes are installed on each host the same as when deployed in the datacenter on a flat layer 2 network.
Multiple Availability Zone Deployment
Highly available clusters are typically split across subnets in different availability zones and require VPC routes for traffic between subnets. Romana avoids the limit on the number of VPC routes (default of 50) which caps the size of clusters that can use native VPC networking.
Network Advertisement in EC2
Romana updates the VPC route table directly via the API. This lets applications use native VPC networking, avoid an overlay and deliver the highest network performance possible.
Initially, Romana adds a route for each node, up to the VPC limit.
For larger clusters, Romana then automatically configures some nodes to forward traffic to other nodes, effectively turning them into routers. Traffic is spread across available nodes to avoid traffic bottlenecks.
Romana performs healthchecks and configures a failover route on instance failure. Robust routing with automatic failover allows users to confidently build HA clusters across availability zones that use native VPC networking.