Load Balancing XDR Proxy Instances with ESP Outbound Connectors

To increase the throughput of XDR Proxy instances that replicate data to another Aerospike cluster, you can deploy a load balancer in front of those instances.

XDR Proxy instances receive change notifications when records are inserted, modified, or deleted in an Aerospike database. The change-notification system uses Aerospike's cross-datacenter replication (XDR) to send notifications when changes to records are made. Since Aerospike Enterprise Edition 5.0, XDR has used a protocol that is TCP based.

TCP-based load balancing cannot balance loads across existing TCP connections to XDR Proxy instances. The connections are sticky, rendering newer XDR Proxy instances useless from a load sharing standpoint.

ESP outbound connector converts XDR messages into HTTP requests so that you can address the TCP stickiness problem by using an HTTP load balancer to distribute HTTP requests to existing and newer nodes. It works across all the deployment options from bare-metal to the cloud, including Kubernetes. It can also handle scenarios where a node is removed.