Teradata database restart? - response (1) by ToddAWalter

When a node fails - that is not currently a spare node - Teradata will restart no matter what the configuration.
If hot spare is available, then the AMPs from the failed node will move to the hot spare automatically and the system will return to operation. There will be no performance impact.
If a hot spare is not available, then the AMPs from the failed node will be distributed among the remaining nodes in the clique. The system will return to operation with all data available but with a performance impact equal to the percentage of the clique the failed node represented (eg 33% for a 3 node clique). This performance impact will be felt in full if the system is operating at full capacity, but will be felt signifcantly less if the system is operating below the full capacity.
A Teradata system always has cliques unless it is a single node system. If the only node in a single node system fails, the system is down until the node is replaced.