ORA-30036: unable to extend segment by string in undo tablespace "string"   tips

It is important to note that ORA-30036 is associated with UNDO tablespaces.  If you use autoextend on an UNDO tablespace  because you can easily run out of UNDO and receive ORA-30036 along with an aborted update. For a full note on UNDO sizing, check my notes on Oracle UNDO sizing.

Question:

I received ORA-30036 after a shutdown.  A job was killed so that we could reboot after it had been running.  We issued the shutdown command but the database didn't stop and then had shutdown abort.  Now, trying to restart we get this:

Errors in file /u0704/oracle/proddb/9.2.0/admin/PROD/udump/prod_ora_16213.trc:
ORA-30036: unable to extend segment by 8 in undo tablespace 'APPS_UNDOTS1'
Error 30036 happened during db open, shutting down database
USER: terminating instance due to error 30036
Instance terminated by USER, pid = 16213
ORA-1092 signalled during: ALTER DATABASE OPEN...

Answer:

The workload had been running for 12 hours  and caused a workload spike.  You received ORA-30036 as the transaction attempted to recover in startup, which caused you to met the UNDO limit.  The ORA-30036 error is thrown as the database refuses to open. 

You can resolve ORA-30036 by first mounting the database and disabling UNDO:

alter system set undo_management = manual scope=spfile;

Next, you must shutdown to resolve ORA-30036 and then startup again using rollback mode and a system rollback segment.  Use UNDO tablespace to add files and then use alter system set undo_management=auto scope=spfile; to activate the UNDO once again.  To fully resolve ORA-30036, shutdown and restart again.