Client tools (such as SQL Server Management Studio) are shared features that are installed on every node of a failover cluster. When a node is added, they get installed on the new node automatically. In case the tools haven't been installed before, you can install them without downtime. By default, the regular installation procedure installs the management tools on the entire cluster (i.e. all the nodes).

On older versions of SQL Server (2008, 2008 R2), installation of the client tools on a node may fail during the pre-installation checks, right after the feature selection. The check states that an instance is already present on the node, of course, stating the obvious.

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