2ndChance

Second Chance 2ndChance™ is an inexpensive insurance policy for retailers using the IBM 46x0 store system with only a single store controller.

2ndChance™ is a background application that periodically checks to see whether or not any sequential file in a user list has changed in length. If the file length has changed, the program mirrors or copies the file on the second hard drive. This provides a backup copy of the file on a second, physical device.

The user has the ability to create a list of files that the application will watch. Each file can be mirrored on a different schedule. The user selected interval is from one second to one hour. This allows the user to balance file activity and store controller workload.



Benefits:
  • The retailer can use less expensive POS configurations with only a single store controller.
  • The retailer has a backup of critical data, such as the T-Log, in the store in case the first hard drive fails or becomes unavailable during the time the store is open.

Why is 2ndChance™ needed?
  • Even though today’s point of sale hard-ware is more reliable than it ever was in the past, the mean time to failure of components is still important. Retailers with chains of small to medium size stores often choose to run their POS system with a single store controller. A large enough number of stores and the law of averages means that failure of a disk drive is a common occurrence in many chains.
  • Failure of a disk drive often wipes out the transaction log of the day’s sales. In order to recover, retailers often had to manually re-enter their journal tapes. The use of electronic journals makes that hard to do, especially if the journal files are stored on the same disk drive as the transaction log.
  • The 2ndChance™ application allows the retailer to decide where to put critical sequential files on the store controller and automatically mirror these files on another disk drive. For those rare times when the hard drive fails, the critical sequential files will be available down to the copy interval chosen by the retailer.

What does 2ndChance™ run on?
  • 2ndChance™ runs on any current version of the IBM 4680 or IBM 4690 Operating System in conjunction with any IBM 4680 / 4690 Sales Application.
  • Any processor platform that supports the base application and operating system will be sufficient to run this enhancement, although faster systems will take less time to backup the files than slower processors.
  • The single processor platform needs to have two (2) hard drives that the user can use. The application can mirror the files in either direction between the two devices.

How does 2ndChance™ work?
  • The retailer decides which sequential files are the most critical, and positions the master copy on either the first or second hard drive. The retailer uses the list building utility to add, delete, and change entries in the automatic backup table. Entries in the table identify the file, how often it needs to be mirrored, and which disk is the source drive and which disk is the target drive.
  • A background timer task periodically looks at the table of entries, which represents the selected files, and decides whether or not the file needs to be mirrored. The retailer can have the files on different copy cycles to match the activity patterns of the file.
  • If a hard drive needs to be replaced, the backup files are on an alternate disk drive waiting to be copied back to the primary disk. This recovery process can be performed manually, but there is also a Restoration program included with 2ndChance™ which can automate the process for you.