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Shadow D/R starts new decade of 3000 database backups

Lund acquired Shadow D/R last year from Carolian Systems, along with customers who have been using the product for years. HP marketed Shadow for HP 3000s as Silhouette before it assumed its current support of the Netbase product.

The Lund software duplicates TurboIMAGE databases by transporting the log file of one primary system to a secondary HP 3000. It then automatically updates the databases on the secondary system so they match those on the primary HP 3000.

The product lets system managers shadow a single 3000 to multiple 3000s, shadow a database residing across multiple 3000s to a single secondary system, or lets two systems mirror each other. One use of the software is to give users 24x7 access to databases by doing backups off the secondary HP 3000.

At Kimberly Clark in Wisconsin, process group team leader Jim Duffy said the manufacturers of goods like Kleenex and paper products have been using Shadow for 10 years. A Series 918 uses a log file from another Series 918, doing real-time data mirroring in a 24x7 environment.
“It just sits there and runs. I wish all our software worked so well. It just does its job, and you can forget about it,” Duffy said.

Employees in the 100-person user base switch a physical switch on the back of their terminals to use the backup system, something that has happened “several times,” in 10 years of use, Duffy said. “When the main system went down, we’d go to the backup and ensure the transactions were complete, and if they weren’t, they’d allow you to back them out,” he said. “Then we tell users to change over the cable and check their last transaction.”

Most of the 40 minutes of downtime “involved going around to check and make sure everybody had changed their cables,” Duffy said. He added that the setup of the system required only about 20 hours, and that he chose the product on the basis of its user friendliness.

Shadow D/R can also be used to balance user workloads on the primary 3000 by using the secondary database in read mode for inquiries. The product is designed exclusively for MPE/iX systems.