Relational Database(rdbms via odbc) Interface

Sample RDBMSPI.bat File

The following is an example file:

REM===========================================================================

REM

REM RDBMSPI.BAT

REM

REM Sample startup file for the Relational Database (RDBMS via ODBC) Interface

REM

REM ===========================================================================

REM

REM OSIsoft recommends using PI ICU to modify startup files.

REM

REM Sample command line

REM

RDBMSPI.exe

/ps=RDBMSPI ^

/id=1 ^

/DSN=Oracle8 ^

/User_ODBC=system ^

/Pass_ODBC= ^

/host=XXXXXX:5450 ^

/f=00:00:05 ^

/f=00:00:10 ^

/f=00:00:15 ^

/Output="C:\Program Files\PIPC\Interfaces\RDBMSPI\Log\RDBMSPI.out" ^

/SQL="C:\Program Files\PIPC\Interfaces\RDBMSPI\SQL\" ^

/DEB=1 ^

/PISDK=1 ^

/Recovery=TS ^

/Recovery_Time=*-5m

REM

REM End of RDBMSPI.bat

18. UniInt Failover Configuration

Introduction

To minimize data loss during a single point of failure within a system, UniInt provides two failover schemas: (1) synchronization through the data source and (2) synchronization through a shared file. Synchronization through the data source is Phase 1, and synchronization through a shared file is Phase 2.

Phase 1 UniInt Failover uses the data source itself to synchronize failover operations and provides a hot failover, no data loss solution when a single point of failure occurs. For this option, the data source must be able to communicate with and provide data for two interfaces simultaneously. Additionally, the failover configuration requires the interface to support outputs.

Note: Phase 1 is appropriate in only two situations: (1) if performance degradation occurs using the shared file or (2) read/write permissions for the shared file cannot be granted to both interfaces.

Phase 2 UniInt Failover uses a shared file to synchronize failover operations and provides for hot, warm, or cold failover. The Phase 2 hot failover configuration provides a no data loss solution for a single point of failure similar to Phase 1. However, in warm and cold failover configurations, you can expect a small period of data loss during a single point of failure transition.

Note: RDBMSPI interface supports UniInt Phase 2 cold failover.

You can also configure the UniInt interface level failover to send data to a High Availability (HA) PI Server collective. The collective provides redundant PI Servers to allow for the uninterrupted collection and presentation of PI time series data. In an HA configuration, PI Servers can be taken down for maintenance or repair. The HA PI Server collective is described in the PI Server Reference Guide.

When configured for UniInt failover, the interface routes all PI data through a state machine. The state machine determines whether to queue data or send it directly to PI depending on the current state of the interface. When the interface is in the active state, data sent through the interface gets routed directly to PI. In the backup state, data from the interface gets queued for a short period. Queued data in the backup interface ensures a no-data loss failover under normal circumstances for Phase 1 and for the hot failover configuration of Phase 2. The same algorithm of queuing events while in backup is used for output data.

Quick Overview

The Quick Overview below may be used to configure this Interface for failover. The failover configuration requires the two copies of the interface participating in failover be installed on different nodes. Users should verify non-failover interface operation as discussed in the Installation Checklist section of this manual prior to configuring the interface for failover operations. If you are not familiar with UniInt failover configuration, return to this section after reading the rest of the UniInt Failover Configuration section in detail. If a failure occurs at any step below, correct the error and start again at the beginning of step 6 Test in the table below. For the discussion below, the first copy of the interface configured and tested will be considered the primary interface and the second copy of the interface configured will be the backup interface.

Configuration

• 
  One Data Source
  
• 
  Two Interfaces
  

Prerequisites

• 
  Interface 1 is the Primary interface for collection of PI data from the data source.
  
• 
  Interface 2 is the Backup interface for collection of PI data from the data source.
  
• 
  You must set up a shared file if using Phase 2 failover..
  
• 
  Phase 2: The shared file must store data for five failover tags:

  (1) Active ID.

  (2) Heartbeat 1.

  (3) Heartbeat 2.

  (4) Device Status 1.

  (5) Device Status 2.

  
  
• 
  Each interface must be configured with two required failover command line parameters: (1) its FailoverID number (/UFO_ID); (2) the FailoverID number of its Backup interface (/UFO_OtherID). You must also specify the name of the PI Server host for exceptions and PI tag updates.
  
• 
  All other configuration parameters for the two interfaces must be identical.
  

Synchronization through a Shared File (Phase 2)

Figure 1: Synchronization through a Shared File (Phase 2) Failover Architecture

The Phase 2 failover architecture is shown in Figure 1 which depicts a typical network setup including the path to the synchronization file located on a File Server (FileSvr). Other configurations may be supported and this figure is used only as an example for the following discussion.

For a more detailed explanation of this synchronization method, see Detailed Explanation of Synchronization through a Shared File (Phase 2)