RFD 93: Robust Access to Nodes (#17676)
RFD 93: Robust Access to Nodes (#17676)

Ensure that users can access nodes via `tsh ssh` when there is intermittent or no connectivity to Auth.

Connectivity to the Auth server is a single point of failure which can result in not being able to access
a resource. If a user already has already obtained a valid certificate (via `tsh login`) there are certain
scenarios when a connection to Auth should not required to gain access to a node. This would reduce the burden
on cluster admins when performing an Auth upgrade. On top of the potential downtime during the upgrade, any issues found as a result of the upgrade require a rollback, which can further extend downtime and lack of connectivity.

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