Alternate File Server - Setup and Implementation as Primary

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To maximize system uptime, RPOWER may (and should) be configured with one or more alternate file servers. In the event of a failure of the primary file server, the system may be re-configured, within minutes, to run from the alternate file server with no loss of data and minimal downtime.

Setup

During the initial installation questionnaire, RPOWER will ask "Do you want this computer to be an alternate file server?" Answer yes to this question on at least one of the non-file server workstations. (It's fine to answer yes on the file server as well.)

The operator will then be prompted "Enter the path that will be shared as the 'Server Root' directory for the the local backup copy of RPOWER". Under all normal circumstances, click OK to accept the offered path C:\SYS. By so designating an alternate file server, during the close day process, the system will copy the entire contents of the primary file server's SYS folder to the corresponding folder on the alternate machine. Note that this is a "Smart" copy, only newer files are actually copied so the process is quite fast except on the initial close day, or after a system upgrade.

RPOWER will then prompt "Do you want a periodic RPOWER data backup to this local drive? Click Yes if this workstation is the first, or primary, alternate file server. Doing so will configure the workstation as a "Hot" backup machine, if addtional alternate file servers will be configured, click No on at least one of them at this prompt to configure it as a "Warm" backup machine. More discussion of "Hot" and "Warm" to follow. Once configured as a periodic backup machine, it will query the primary file server once a minute to determine if any of the files found in C:\SYS\RPOWER\DATA have changed since the last query. Because of the sequential record structure of RPOWER's dBase data files, only the New Records found in any changed file are sent to the backup machine, NOT the entire file, saving considerable time and network overhead.

  • Important Note: If a workstation will be designated a a periodic backup machine it should also run a background RPOWER, i.e. the answer to the first question asked by the questionnaire: "Run a background RPOWER (for backup, SQL Data, Online Ordering, etc.)? should be Yes.

To review: A "Hot" alternate file server will have its entire SYS folder mirrored to that of the primary file server during the close day process. Then, during the business day, as records are changed in and added to RPOWER's data files, those records are once a minute copied to the alternate machine, meaning it is literally ready "Up to the Minute" to take over as the primary file server. A "Warm" alternate file server also has its entire SYS folder mirrored to that of the file server during close day, but its DATA files are NOT continually updated during the business day so as not to immediately propogate any data corruption, as unlikely as that corruption may be.

  • Note: In addition to following the above procedures, the SYS folder of the "Hot" machine should also be shared in Windows, with full read and write privileges.

Implementation of Fail-Over

  • Note: While it would be very feasible for RPOWER itself to implement an automatic fail-over in the event of failure of the primary file server, an active decision has been made to not go that route. It is our feeling that any apparent failure of the primary file server should be diagnosed and corrected by qualified support personnel, lessening the chance that something as simple as a loose ethernet cable escalate to a major situation.

After confirming that an actual and irrecoverable failure of the primary file server has occurred, the "Hot" alternate file server must have its C:\SYS folder substituted. Step one is identifying the correct workstation. Confirming The presence of a C:\SYS folder with current (based on Date Modified) data files in its DATA folder is one method. Reviewing workstaion .ini files for the presence of the lines:

 K3LOCBU=C:\SYS\RPOWER\DATA
 K3ASBROOT=C:\SYS
 K3LOCTM=1,1

will also confirm the identity of an alternate file server.

Check that the SYS folder is being shared with full permissions.

Then, from Windows Explorer on that workstation navigate to:

 C:\SYS\RPOWER\WINRUN

and execute _Make_File_Server.wsf.

At the Enter the path... prompt, click OK.

At the Enter the drive letter... prompt, click ok.

(or enter a drive letter if the default, R, is not suitable)

At the Ready to make.. prompt, click OK.

At the To prevent accidental execution... prompt, click NO.

At the This computer can now be an RPOWER... prompt, click OK.

Now execute RPOWER normally from the new file server. Then, at the client machines, through My Network Places, navigate to the Sys folder on the new file server and execute RPOWER.

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