DMP events are handled by vxesd (Veritas Event Source Daemon).
So DMP logs are written by vxesd.

When vxesd is started, the user can indicate which file is used for the DMP events log.
If not specified, "/etc/vx/dmpevents.log" file is used by default.

When the DMP event is handled, the log level of each DMP event is checked and compared with the DMP_LOG_LEVEL set by the user.

Note: DMP_LOG_LEVEL can be checked by running 'vxdmpadm gettune DMP_LOG_LEVEL'.

If DMP_LOG_LEVEL is equal to the log level of each DMP or higher than this, the DMP event is written to DMP event log files.
For example, if the log level of a DMP event is 2 and DMP_LOG_LEVEL is 4, then this DMP event is written to DMP event log files.

Note: DMP_LOG_LEVEL is set to 1, 2, 3, or 4. But sometimes, it can be set to 5,6,7 or 8.
      The default value of DMP_LOG_LEVEL is 1.

If the number of lines in the DMP event log file reaches 1000, then this event log file is moved to the backup file and a new DMP event log file is created.
For example, if there are three DMP event files including back files like below,
   /etc/vx/dmpevents.log
           dmpevents.log.0
           dmpevents.log.1

then each file is moved like below,
  
     dmpevents.log.1  -->  dmpevents.log.2
     dmpevents.log.0  -->  dmpevents.log.1
     dmpevents.log    -->  dmpevents.log.0
    

And a new 'dmpevents.log' file is created.

The DMP event log files can be moved to dmpevents.log.9.
If the backup operation occurs once more, the oldest DMP event log file (dmpevents.log.9) is deleted.

So the life of the DMP event log file is like below,
   dmpevents.log --> dmpevents.log.0 --> dmpevents.log.1 --> ...... --> dmpevents.log.9 --> then deleted.

Applies To

OS: All platform
VM: 5.0 or higher