WatchDog

  

WatchDog is an application that can ‘watch’ other applications to ensure they are actively running. If an application should shutdown abnormally or become hung, WatchDog can restart this application.

WatchDog is an optional purchase item that can be associated with DAD, DropBox and Gateway.   

 

Overview

WatchDog utilizes a heartbeat between the target application and itself. If the target application cannot ‘respond’ to the heartbeat, WatchDog will restart the program. An example would be if the target program were ‘Not Responding’.

WatchDog also monitors an EXIT file. When the target application is exited normally, that program will create an EXIT file. Presence of this file allows WatchDog to determine if the closure of the program was intentional.  If the target application should exit from an error, the EXIT file is not created. At this point, WatchDog will restart the program.

NOTE: WatchDog will not be able to monitor any generic process. Currently only DAD, DropBox and Gateway can be monitored.  

 

WatchDog only monitors Target applications on the machine for which it is being run. WatchDog will not monitor a process on another workstation.  

 

The WatchDog screen displays the current status of all Target applications. Basic information such as Process Name along with Process Pathname and working directory are shown.

The current Status of the Process is shown as either ‘Running’ or ‘Not Running’. If the Target Process is not supported on the Security key, ‘No Support for Process’ will be displayed.  

An continually updated Heartbeat will be displayed as Boom and BaBoom. If a Heartbeat is missed, it is displayed with the number of attempts tried. When the number of misses equals the number of maximum attempts defined by the WatchDog.INI file, WatchDog will restart the program.

The number of times the Target program has been restarted is also logged.  

The Enabled / Disabled button allows on to Enable or Disable the heartbeat communications between WatchDog and the Target application. When Enabled, WatchDog will monitor the program, likewise, when Disabled WatchDog will cease to monitor the program.

To the right of the screen are the Target applications being monitored. Selecting one of the Targets will display its status information.  

Logs

WatchDog will generate a log [WatchDog.LOG] in the directory it is run from. This log contains information about when a process has stopped responding to a heartbeat, when it was restarted along with information about when a process has been manually shut down. 

The following are examples of WatchDog log enties.

WatchDog LOG entry

Description of entry

01/27/05 15:32:16 Started WatchDog
01/27/05 15:36:38 Shutdown WatchDog

WatchDog has been Started and Stopped

01/27/05 15:33:56 w[1] WARNING: Process not running (DAD.exe)
01/27/05 15:33:56 w[1] ERROR: Unable to start process (DAD.exe)

WatchDog has detected that DAD is no longer running. When it is unable to start <check> the process, it will restart the application.

01/27/05 15:35:06 w[1] WARNING: Process not running (DAD.exe)
01/27/05 15:35:06 w[1] NORMAL : Detected normal exit (DAD.exe)

WatchDog has detected that DAD is no longer running. Here it detected that the program was manually exited and shut down normally.

01/27/05 15:38:32 w[1] WARNING: Unable to detect heartbeat (DAD.exe)

This message indicates that the heartbeat for the application can not be found.

01/27/05 15:38:51 w[2] NORMAL : Process started (Dist-WO.exe)

WatchDog is starting an application that was not running when WatchDog was started.

01/27/05 15:39:19 w[2] WARNING: Killing process (dropbox.exe)

This entry will be entered if WatchDog terminates a program because the process is not responding to heartbeats.

 

Configuration

Setting WatchDog to monitor an application involves configuring an INI file for both WatchDog and the Target program. 

WatchDog is configured via the C:\DAD\WatchDog.INI file. Target applications such as DAD, DropBox and Gateway/Dist also utilize an INI file to communicate with WatchDog. 

This is done via the WatchDAD.INI, WatchDrop.INI and WatchGate.INI files which can be found within the C:\DAD, C:\DAD\DropBox and C:\Gateway directories respectively.

WatchDog.INI variables are settings are defined as follows:

VARIABLE

VALUE

DESCRIPTION

[Watch-1]

 

First instance of WatchDog Target application settings.

Process Name

DAD.EXE

Target applications Process name

Process Full Pathname

C:\DAD\DADNET.BAT

Start path to the Target application

Process Working Directory

C:\DAD

Directory of Target application 

Heartbeat Period

5000

Delay in milliseconds between Heartbeat scans. 

NOTE: This value must be greater than the Heartbeat Period time defined in the Programs INI file. For example, the WatchDAD.INI file should have a Heartbeat Period value of less than 5000. 

Heartbeat Delay

2000

Delay in milliseconds between checks of the Target applications heartbeat.

Heartbeat Max

3

Number of retry attempts of the Heartbeat before restarting the Target application

Watch Disabled

FALSE

True = Disables monitoring of Target application

False = Default mode

[Watch-2]

[Watch-3]

 

Second and Third instance of WatchDog Target application settings.  

NOTE: This all other Variable INI entries will be the same with the Values being for the Second and Third Target application 

In addition to the WatchDog INI file, DAD, DropBox and Gateway/Dist each use an INI file, which allow for communication back to the WatchDog program. These INI files are WatchDAD, WatchDrop and WatchGate respectively. Each of these files will be created in the root of the \DAD, \DROPBOX and \GATEWAY directories.

VARIABLE

VALUE

DESCRIPTION

[Watch]

 

 

Process Name

WATCHDOG.EXE

Process name of WatchDog

Process Full Pathname

C:\DAD\WATCHDOG.EXE

Start path to the WatchDog application. 

When DAD starts and WatchDog is NOT running, DAD will automatically start the WatchDog program. 

Process Working Directory

C:\DAD\WATCHDOG

Directory of WatchDog. This path must be set so DAD can clear the Heartbeat file. 

Heartbeat Period

1000

Heartbeat response time in milliseconds. 

NOTE: This value must be less than the Heartbeat Period time defined in the WatchDog INI file. For example, the WatchDog.INI file should have a Heartbeat Period value of greater than 1000.