Node Failure Issues
Node failures can occur on either Teradata Database single-node systems or Teradata Database MPP systems, but the failure is handled differently.
For information on how node failures are handled for Teradata Database MPP systems, see Node Failure Recovery (MPP Only).
- If hardware issues occur on the host, Microsoft Azure migrates the VMs to other hosts.
- If platform issues occur, such as Hypervisor or guest agent issues, the VM may be restarted.
- If planned maintenance is scheduled, updates to the host occur that may pause the VM for about 30 seconds after which the VM becomes available again. For some updates, the VM may be restarted.
For unexpected restarts, check the Azure Activity Log. If you do not find information related to the restart, create an Azure support request to see if Azure can look for issues in their backend availability logs. See Azure Documentation Center.
There are dozens of reasons for a node failure on single-node systems and it may be difficult for you to determine the cause. If your VM does not automatically restart after 10 minutes, first check the alerts in Teradata Server Management or Teradata Viewpoint. If a kernel fails or becomes unresponsive due to Azure Guest OS issues, the failed node is not automatically recovered and may require manual debugging. For assistance, contact Teradata Customer Support.