Core files have the habit to be scattered all over the server, depending on what processes are running, what the working directories are of processes, and which of the processes dump a core file. That is often very annoying, and you may have to use the find command to find all the core files to clean them up.

There is a way to create a centralized repository for your core files, and you can use some not so very well known user settings to do just that.

First, create a location where you can store core files, for example, create a file system /corefiles with plenty of space:

# df -g /corefiles
Filesystem    GB blocks      Free %Used    Iused %Iused Mounted on
/dev/corefilelv     19.92      8.56   58%       94     1% /corefiles

Now, change the default core settings to point to this location:

# chsec -f /etc/security/user -s default -a core_path=on -a core_pathname=/corefiles -a core_compress=on -a core_naming=on

The command above changes the default settings for the core files - for all users. You can obviously do the same for individual users instead, just change "default" to whatever user you want to set this for.

The four options in the chsec command above are:

core_compress

Enables or disables core file compression. Valid values for this attribute are On and Off. If this attribute has a value of On, compression is enabled; otherwise, compression is disabled. The default value of this attribute is Off. This will help you save disk space.

core_path

Enables or disables core file path specification. Valid values for this attribute are On and Off. If this attribute has a value of On, core files will be placed in the directory specified by core_pathname (the feature is enabled); otherwise, core files are placed in the user's current working directory. The default value of this attribute is Off. You'll need to set this if you wish to specify a specific directory to store core files.

core_pathname

Specifies a location to be used to place core files, if the core_path attribute is set to On. If this is not set and core_path is set to On, core files will be placed in the user's current working directory. This attribute is limited to 256 characters. This is where you specifiy the directory to store core files.

core_naming

Selects a choice of core file naming strategies. Valid values for this attribute are On and Off. A value of On enables core file naming in the form core.pid.time, which is the same as what the CORE_NAMING environment variable does. A value of Off uses the default name of core. This will create core files with the name in a form of core.pid.time, where time is ddhhmmss (pid = the process id; dd = day of the month, hh = hours, mm = mintues, ss = seconds). You can leave out this option and instead set environment variable CORE_NAMING to true.

Doing so - and after restarting any applications (or the whole server), your core files should now be all stored in /corefiles - that is, if you have any processes that generate core files of course.

Note: The same can be achieved with the chcore command:

# chcore -c on -p on -l /corefiles -n on -d

Validate the settings as follows:

# grep -p default /etc/security/user | grep core
        core_compress = on
        core_path = on
        core_naming = on
        core_pathname = /corefiles

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