OCI-59107
An instance in the cluster is not ready to enable Oracle RAC Two-Stage Rolling Updates
Cause
A new instance might have joined the cluster while ALTER SYSTEM [ENABLE | DISABLE] RAC TWO_STAGE ROLLING UPDATES statement is in progress.
Another reason for this error could be a temporary network outage.
Action
Retry the ALTER SYSTEM [ENABLE | DISABLE] RAC TWO_STAGE ROLLING UPDATES statement.