Space Group Operations in Tanzu Hub Can Resolve to an Unexpected Foundation in Multi-Foundation Environments

Products

• VMware Tanzu Platform Core

Issue/Introduction

In Tanzu Hub environments with multiple attached Cloud Foundry foundations, a space group operation can behave differently than expected. For example, it can appear that a fix is missing from the current foundation release (because the operation is actually being resolved on a different foundation). An application push might fail even though it is expected to succeed, because it was deployed on an older Elastic Application Runtime (EAR) foundation.

This can occur when the Tanzu cf CLI is pointed to the Tanzu Hub API rather than to a specific foundation API. Because Tanzu Hub uses org groups and space groups as cross-foundation constructs, an org group can span multiple foundations. In Tanzu Hub releases earlier than 10.4, space group creation automatically selects a single foundation in the org group’s associated foundation group. This will cause the space group, and subsequent operations against it, to be resolved on a different foundation than expected.

Environment

 

• Tanzu Hub with multiple attached Cloud Foundry foundations.
• Org groups and space groups managed through Tanzu Hub.
• Mixed foundation versions, where one attached foundation includes a fix and another does not.

 

Cause

Before Tanzu Hub 10.4, when creating a space group, the foundation selection is automatic. As described in the Hub Web UI, “A space will be created automatically on a foundation in the Org Group's associated Foundation Group.” In this model, there is no option to explicitly pin the space group to a specific foundation during creation.

As a result, in a multi-foundation org group, a space group operation can land on an attached foundation other than the one the user expected. If the selected foundation is on an older release, the behavior can look like a regression or a missing fix, even though the fix is present on a different attached foundation.

Resolution

For Tanzu Hub versions earlier than 10.4, there is no method to explicitly force foundation selection during space group creation. In these versions, troubleshoot by identifying all foundations associated with the org group and verifying which foundation actually received the space group or operation.

Starting in Tanzu Hub 10.4, space group creation supports explicit placement controls. The documented workflow includes Auto and Manual replica placement, selection of one or more foundation groups or foundations, and, for manual placement, selection of the specific foundations where replicas are created. This allows the target foundation to be pinned instead of relying only on automatic selection.

Where deterministic foundation placement is required, upgrade to Tanzu Hub 10.4 or later and use the space group placement options to select the intended foundation.

Additional Information

You cah check in Tanzu Hub Web UI, in the space groups section, which foundation the space belongs to.