Chapter 5. Skupper load balancing and failover

A multi-key listener provides per-service control over load balancing and failover by binding a single endpoint to multiple routing keys (connectors). This is the recommended approach for most use cases because it offers:

For configuration details and examples, see Creating a multi-key listener using YAML.

Link cost is a configurable integer value that influences how Skupper routes traffic across all services that traverse a link between two sites. The routing algorithm favors paths with the lowest total cost from client to target server.

📌 NOTE Link cost applies to all services on a link and cannot be set differently for individual services. For per-service control, use a multi-key listener instead.

Understanding link cost behavior

Using link cost for failover

You can configure link cost so that a primary location handles all traffic until failure, then traffic fails over to a backup location. To achieve this, set the cost from the client to the backup server very high, for example 99999:

In this configuration, all connections are routed to the local server. If the local server becomes unavailable, traffic fails over to the remote server regardless of the high cost.

📌 NOTE Skupper does not provide orchestrated failover for stateful applications that require control over the order in which traffic is redirected. You must implement that orchestration separately.

For details on configuring link cost, see: