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Don Burleson Blog 







ORA-00344 Unable to Re-create Online Log

Expert Oracle Database Tips by Donald BurlesonApril 6, 2015


Question:  I am trying to clone my database and I get the ORA-00344 error:

***** got the following errors ****
ERROR at line 1:

ORA-00344: unable to re-create online log 'u01/oradata/prod/logs/redo01b.ora'
ORA-27040: skgfrcre: create error, unable to create file
OSD-04002: unable to open file
O/S-Error: (OS 5) Access is denied.

How do I resolve the ORA-00344 error?

Answer:   You start by using the oerr utility to look up ORA-00344 and ORA-27040 errors:

ORA-00344: unable to re-create online log 'string'  

An I/O failure occurred when attempting to re-create an online as part of either ALTER DATABASE OPEN RESETLOGS or ALTER DATABASE CLEAR LOGFILE command.

Action: Correct the file/device as indicated by accompanying errors  

Here are details on the ORA-27040 error:  

ORA-27040: file create error, unable to create file  

Cause: create system call returned an error, unable to create file  

: verify filename, and permissions  

In this case, The Oracle background processes do not have the necessary OS permissions to create a new file in the directory.  

To troubleshoot ORA-27040 errors, you need to test from the OS.

You need to check these disk issues:  

  • Missing mount-point or Windows drive letter:  In another condition, a non-existent mount point (or non-existent disk) can cause these errors:

ORA-00344: unable to re-create online log 'D:\ORADATA\PROD\REDO01B.ORA'
ORA-27040: skgfrcre: create error, unable to create file
OSD-04002: unable to open file
O/S-Error: (OS 5) Access is denied.

In the above case, the PC does not have a D: drive mapped to Windows.

  • Incorrect OS Permissions - The directory owner should be your "oracle" user, and the permission should be at least 770, to allow the Oracle user and ensure that the is in the dba UNIX group.  A permission of 770 on the directory should allow you to allocate files within the mount point.  You can issue the chmod 770 on the directory node to correct the permissions:

    oracle> cd 'u01/oradata/prod
    oracle>  chmod 770 logs

  • Not enough Disk Space - You need to check the Filesystem space and ensure that there is enough room within the directory using the ?df ?k? command.   In  Windows, go to "Computer -->  Disks  --> (and right click on disk letter)

For more information on using OS commands, see the book Oracle Shell Scripting

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