Local storage is temporary or ephemeral, but provides better performance compared to EBS. It is ideal for testing and development where you do not need to keep data. The storage is used for the data volume, but the root disk uses 350 GB EBS. A minimal charge occurs at the time you deploy any instance that uses a root disk.
Consider the following when choosing the local storage.
| Local Storage Type | Considerations |
|---|---|
| Local (both SSD and HDD) |
|
| SSD Only |
|
| HDD Only |
|
Local storage leads to data loss in the following node events:
- Shutdown (init 0)
- Node hang
- Machine check (hardware fault such as a double bit memory error)
- Stopping the instance through the Amazon EC2 Console
- Terminating an instance
Data loss does not occur with certain node events, such as a reboot (init 6) or node panic (sometimes referred to as an oops event). An oops event causes a memory dump and then the node is rebooted.
To avoid data loss, deploy a Vantage instance from an EBS-based AMI, or use an automated Teradata backup solution such as Teradata Data Stream Controller.