Mirror administration page does not render on all cluster nodes

Summary

When installing a new mirror in a Bitbucket Server cluster, the mirror administration page displays an error on one or more cluster nodes. The mirror configuration page will render correctly on at least one cluster node.

Workaround

Navigate to admin > manage add-ons on the cluster nodes, each will show a connect add-on for the mirror. On the successful node, the add-on will be enabled. On the problematic node(s), the add-on is displayed as not enabled. Clicking ‘Enable’ to enable it on the problematic node resolves the problem.