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Introduction:

Managing the short term history file, one need to be very careful how to configure the system so that the short term history is not compromised.

Care is required to set the correct disk space and to avoid performance issues caused by data loss.

                                           

                                                                       

By default the short term history is pruned every 24 hours by the Warehouse proxy agent (WPA).

This is the uploading of historical information to the Data Warehouse, pushed from the agent via the Warehouse Proxy Agent and deletion of the uploaded information from the short-term history file. 

                                                                        

Each phase must be completed successfully for the next phase to run.   

Hence, if the agent cannot communicate with the WPA, for example due to a network outage, data is not deleted from the short-term history files. This will result in the file size growing unrestricted. This in-turn may compromise the stability of the managed system due to a lack of disk space on the file system.                                        

                                                                        

So when you have data older than 24 hours then check if there was a communication issue or any outage of the either the agent or WPA             

                                                                       

From ITM 6.2 new feature was added to ITM to enable a size threshold to be defined for the short-term history files.                           

                                                                       

The solution to prevent the unrestricted growth of the short-term history files is based on two environment variables:                   

                                                                       

KHD_TOTAL_HIST_MAXSIZE:                                                

The maximum size threshold, in megabytes, for the short-term history files. This threshold is based on the combined size of the short-term history files for all agents running on the managed system.            

                                                                        

                                                                       

KHD_HISTSIZE_EVAL_INTERVAL:                                            

The interval, in seconds, at which the threshold is checked. This has a

minimum value of 60 seconds, and a default of 900 seconds (15 minutes).

                                                                       

These variables must be defined for each ITM agent collecting historical data on a given managed system, it is recommended they are defined in a generic configuration file and that file is referenced from each of the agent specific configuration files. This method minimises the required administration where multiple agents are collecting historical data on a single managed system.                            

                                                                       

Here is an example for a Windows system collecting historical data from

the Windows OS Agent and a Universal Agent Application, firstly, create

a generic configuration file named %CANDLEHOME%TMAITM6GENENV with the following content:                                                     

                                                                       

KHD_TOTAL_HIST_MAXSIZE=4                                                

KHD_HISTSIZE_EVAL_INTERVAL=300                                         

                                                                       

Note: This example will restrict the short-term history files to less  

than 4MB, and the threshold will be checked every 5 minutes (300       

seconds).                                                              

                                                                       

Each of the agent environment variable files, i.e. files KNTENV and    

KUMENV located in the directory %CANDLEHOME%TMAITM6, must be updated with the following environment variable setting:                       

KBB_ENVPATH=C:\IBM\ITM\TMAITM6_x64\TMAITM6GENENV                                      

                                                                       

Note, this assumes the default installation directory for ITM on       

Windows, and both agents will need to be restarted for the restriction 

to apply.                                                              

                                                                       

Similarly, on a Linux platform, the environment variables              

KHD_TOTAL_HIST_MAXSIZE and KHD_HISTSIZE_EVAL_INTERVAL may be defined in a generic configuration file $CANDLEHOME/config/generic.cfg. 

        

This file can then be referenced by each agent, for example in the     

Linux OS Agent configuration file $CANDLEHOME/config/lz.ini as such:   

KBB_ENVPATH=$CANDLEHOME$/config/generic.cfg                            

The Linux agent must be stopped, reconfigured and restarted for the updates to take effect. Any subsequent changes to the file generic.cfg would only require an agent restart.                                   

                                                                       

The customer will need a means of monitoring that the threshold is not 

breached.

For this a simple situation can be setup to monitor this threshold and sent an event before the threshold is reached.                         

                                                                       

Useful link:

http://www-01.ibm.com/support/docview.wss?uid=swg21384435

 

 

 

 

 

 

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