Teradata database instance with local storage on AWS not working after shutdown the instance

Problem:

# pdestate -a

PDE state is RUN/READY.

DBS state is 0/-1: DBS is not running

 # verify_pdisks

      Error:  Cannot open /dev/pdisk/dsk1.

      Error:  Cannot open /dev/pdisk/dsk3.

      Error:  Cannot open /dev/pdisk/dsk0.

      Error:  Cannot open /dev/pdisk/dsk2.

      *****4 error(s) found during pdisk verification*****

 

Reason:

Amazon EC2 Instance Local Storage is temporary or ephemeral. Local storage is ideal for test and development where keeping data is not needed. On Teradata database instance with local storage, data loss does occur for following events (Teradata, 2016).

  • Shutdown (init 0 or shutdown -h / -P or halt or poweroff)
  • Node hang
  • Machine check (hardware fault such as a double bit memory error)
  • Underlying disk drive failure
  • Stopping an instance through Amazon EC2 Console
  • Terminating an instance through Amazon EC2 Console


Data loss does not occur with events, such as reboot (init 6 or shutdown -r) or node panic (oops event).

 

Solution:

There is no solution for it, so you have to terminate the broken instance and start a new instance, and configure the database again.  There is an easy workaround to make your broken database work instead of terminating or recreating the instance.

 

Easy Workaround:

# tpareset -x bringing down the database

        You are about to shutdown the database

                 on the system

                    'DBATest'

        Do you wish to continue (default: n) [y,n] y

# pdestate -a

PDE state is DOWN/UNLOAD.

 

# tdc-init --force_config

-DONE!                                                                                                                                                                                                                      18:32/30:00 EET

[/] [################################################################################################################################################################################################################################] Done!

WARNING:: DBC password has not been changed. DBC password MUST be changed to enable the database service. Please run tdc-start command to change the DBC password and enable the database service.

 

# tdc-start

==================================================================

                       Start Teradata Database

----------------------------------------------------------------------

PDE state is RUN/STARTED.

DBS state is 5: Logons are enabled - The system is quiescent

 

==================================================================

                     Change Teradata System Name

----------------------------------------------------------------------

The current system name is [localhost].

Do you want to change the system name?  [yes/no] no

System name not changed.

 

==================================================================

                     Change DBC Default Password

----------------------------------------------------------------------

New Password:

Retype New Password:

DBC default password successfully changed.

===================================================================

                       Enable Database Service

----------------------------------------------------------------------

Database service started on port: 1025

 

# pdestate -a

PDE state is RUN/STARTED.

DBS state is 5: Logons are enabled - The system is quiescent

 

References

Teradata. (2016, 04 11). Retrieved from http://knowledge.teradata.com/KCS/id/KCS001454

 

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