Setting a Secure Default Directory for Shared Memory Dumps

The DUMPDIR configuration parameter specifies the directory into which Extended Parallel Server dumps shared memory, gcore files, and messages from failed assertions. If you set DUMPDIR to a valid directory, the database server uses that directory. If the specified directory does not have secure 770 permissions, the database server prints a warning message similar to following in its message log file:

[001] 11:01:14  Warning: ONCONFIG dump directory (DUMPDIR) '/tmp' has  
                   insecure permissions

For XPS releases earlier than Version 8.51, the default DUMPDIR setting was /tmp. Because some of the files written to the directory that DUMPDIR specifies can contain sensitive information, the default has been changed to $INFORMIXDIR/tmp, a directory set with 770 permissions to protect data security. If you specify no value for DUMPDIR in the configuration file, this default takes effect, and a message similar to following is printed in the database server message log file:

        [002] 19:18:41  DUMPDIR parameter not specified in ONCONFIG. 
                   Setting it to default '/informix/tmp'

If you set DUMPDIR to a directory that does not exist, the database server automatically resets DUMPDIR to the default $INFORMIXDIR/tmp value, and sets STDERR to a message indicating that the specified value of DUMPDIR was invalid in ONCONFIG, and is being reset to this default.

Although this default value specifies a secure file system, use of this default directory is not recommended, because dumps of shared memory can consume all the available space in the $INFORMIXDIR file system where the database server is installed. Rather than rely on the default DUMPDIR setting, the DBSA should set DUMPDIR to a secure file system that has sufficient space to store dumps of shared memory, gcore files, and messages from assertion failures.