Many of the tools available for mainframes to control and manage data don’t yet exist in client/server database systems. Tools for monitoring, measuring, testing, evaluating and simulating the performance of the database under different allocation formats “will either not be there or will be significantly less powerful than what’s on the mainframe,” said George Schussel, president of Digital Consulting Inc., an Andover, Mass., consulting firm.
Granted, most client/server database-management systems come with tools for defining a database, allocating space for it, defining tables and adding users. A database-management system can also be expected to provide some functions for maintaining the system, such as backing out of a transaction if there’s a failure. The mechanisms should be sophisticated enough to back up the database while on-line, according to Max Dolgicer, a director for Tucker Network Technologies Inc., a consultancy in South Norwalk, Conn.
Yet the client/server platform, arguably a more flexible and cost-effective computing architecture than the mainframe, is woefully lacking in areas of planning and administration.
“We’ve had to create our own security utilities to allow people to access different parts of the application,” said Bill Soper, manager of information services for Chevron Canada, an oil firm in Vancouver, B.C.
Throw hardware at the problem
How do corporate architects of client/server platforms get over such hurdles? By throwing hardware at the problem. “Because you do not have the tools to tell you what hardware to get, you should figure out what you think you’ll need, then triple it — get three times what you think you need for disk capacity — because it’s cheap,” said Schussel.
It’s not enough just to have a large hard disk — administrators should also ensure data redundancy by using mirroring technology to copy data from the disk to a second disk drive, or use a Redundant Arrays of Inexpensive Disks (RAID) system.
To extend the life of the system, make sure the database-management system selected can run on more powerful processors as they become available. “The key is to have a scalable back end so if you top out, you can move to a more powerful platform,” Soper said.
As with any type of server, the client/server back end should be protected by an uninterruptible power supply (UPS). UPS devices generally range in power from 500 kilowatt voltage amps (kva) to 1,500 kva, and they cost between $1,000 and $10,000.
And network-management software is a must. “Network-management tools are still not what everyone would like them to be, but you can piece together enough of a solution to get by,” said Maureen Rogers, director of marketing for Softbridge Inc., a developer of test software for custom client/server applications.
By adhering to such tenets, rightsizing pioneers like Richmond Savings Credit Union have managed to reengineer their business systems without putting their companies at risk, and without using fully redundant, high-priced systems.
Richmond Savings moved its banking system five years ago from a proprietary minicomputer to a 486-based client/server platform that is currently humming along at 100,000 transactions a day. Richmond is using a database-management system called Probe, developed by Prologic Computer Corp., of Vancouver, B.C., that has its own front end. Probe is a combination fourth-generation language, relational database-management system and proprietary network operating system. Prologic is currently helping Richmond crea te links between Probe and NetWare.
“[Prologic] made it so that using DOS, we could create very large databases and have it perform well,” said Allen Lacroix, vice president of technology at the credit union, in Richmond, B.C.
For its central server, Richmond administrators chose a 33MHz 486-based machine with 16M bytes of memory and 3.2G bytes of unformatted disk. Although the administrators looked at RAID disks, they felt they did not need them. “Our database is very reliable, and there are several recovery mechanisms available with it,” said Lacroix.
Another Prologic customer who transferred a credit-union banking system from a mainframe to a client/server platform went further in adding redundancy. The Pacific IBM Employees Federal Credit Union in San Jose, Calif., is using two identically configured IBM PS/2 Model 95s as a central server, said Daryl Tanner, president.
“There are two Model 95s sitting side by side, with one doing nighttime processing. In the morning, we copy one disk over to the other machine, so they both have the same data at the start of the day. If one crashes, we have the other,” he said.