ComputeServer and ComputeNode (routing)

Override the default compute path. Pin to an explicit URL or a named compute node.

Category: connection-string

Syntax

ComputeServer=<url> | ComputeNode=<entity_ref>

Description

## Default behaviour With neither key set, the driver authenticates against the control plane and asks for a compute recommendation. The control plane returns the URL of a node based on its routing policy. The data path then runs against that node for the lifetime of the connection. ## When to override - **Single-node deployments**: only one compute node exists. Set `ComputeServer=` to that node's URL and the driver skips the recommendation round-trip. - **Workload pinning**: a BI tool's queries should run against a specific node. Set `ComputeNode=` to the entity reference; the driver resolves the URL via the control plane. - **Development**: pointing every connection at a local embedded node bypasses cluster routing entirely. ## Choosing between ComputeServer and ComputeNode Use `ComputeServer=` when you know the URL and the deployment topology is stable (URLs do not change). Use `ComputeNode=` when nodes are addressed by logical name and the URL behind it might change (rolling deploys, IP rotation). The entity-ref lookup is one extra round-trip at connect time. ## Failover Neither key implements client-side failover. If the pinned node is unreachable, the connection fails. For automatic failover, omit both keys and let the control plane recommend a node.

Parameters

Name	Type	Description
`ComputeServer`		Absolute URL of a specific compute endpoint. Bypasses the control plane's compute recommendation. Useful for development against a single embedded node, or for pinning a BI tool to a known instance.
`ComputeNode`		An entity reference such as `node::embedded::primary`. The driver resolves the URL via the control plane's node registry and pins all queries on this connection to that node.

Examples

# Pin to a specific instance by URL
Server=https://df.example.com;ComputeServer=https://compute-3.df.example.com:9224

# Pin by entity ref (driver resolves the URL)
Server=https://df.example.com;ComputeNode=node::cluster-prod::worker-7

# Default (no override): the control plane recommends a node
Server=https://df.example.com

Pitfalls

An entity reference passed to `ComputeNode=` that the control plane does not recognise produces a connection error. Use the GUI's **Compute Nodes** page or `delta-forge-cli list-compute-nodes` to enumerate valid refs.
A `ComputeServer=` URL that the BI tool's host cannot reach (firewall, network zone) fails at first request. The control-plane connection succeeds first, so the failure surfaces only when the first query runs.