Teradata Database Fold and Unfold
You can add or remove nodes from an existing system. Adding nodes is referred to as unfolding. Removing nodes is referred to as folding. Folding and unfolding supports only premium storage. A system can always be folded back after unfolding. This feature only applies to the Base, Advanced and Enterprise tiers, and is supported on Teradata Database 5.0 and later.
- Increases the performance of the system by adding more CPU and memory, and increases the storage bandwidth by decreasing the data disks managed per node.
- Increases the node count by provisioning additional VMs and other resources causing an increase in infrastructure and software costs.
- Consumes additional subnet space. The subnet must have enough IP addresses for the new VMs being added to the system.
- Migrates the premium data disks from existing VMs to new VMs.
- Decreases the performance of the system by removing CPU and memory, and decreases the storage bandwidth by increasing the data disks managed per node.
- Decreases the node count by terminating VMs that are no longer needed and associated resources causing a decrease in infrastructure and software costs.
- Migrates the premium data disks from the nodes that are removed to the remaining nodes.
The database capacity and AMP count does not change. When folding and unfolding, the number of AMPs gets redistributed evenly across the nodes.
If either fold or unfold cannot complete successfully, the process automatically attempts to roll back the operation and restore the original configuration. If roll back fails, contact Teradata Customer Support.
To fold or unfold, see the instructions in the table below. Before folding or unfolding, you may need to increase Azure service limits.
|To unfold at launch||Deploying a Teradata Ecosystem from a Solution Template|
|To fold at launch||You cannot fold at launch. You must fold after launch.|
|To unfold after launch||Unfolding a System|
|To fold after launch||Folding a System|