Ameren Corp. is a utility holding company headquartered in St. Louis, MO. Through its subsidiaries, Ameren provides electricity in Illinois and Missouri to approximately 2.4 million electric customers and nearly 1 million natural gas customers across 64,000 square miles. The company’s approximately 9,300 employees support 16,500 megawatts of electrical power generation, 7,400 circuit miles of high-voltage transmission lines, and more than 78,000 miles of distribution—making Ameren one of the larger power companies in Illinois and Missouri.
Like most large companies, Ameren can’t afford to have its mainframe down for extended periods. Power companies must maintain high-availability of electricity and gas to their customers, while also performing normal business functions such as providing online access to accounts, creating monthly bills, and collecting payments. Employees and managers also need access to business information to properly run the company and serve customers. The Information Technology (IT) department and the services it provides are as important and integral to the business as the electricity and gas the company delivers to customers.
Maintaining the high-availability required of Ameren’s IT department sometimes poses significant challenges. Recently, a difficult challenge arose when business requirements dictated a storage device migration to newer equipment.
“Our goal was to implement a tiered storage environment to reduce electricity consumption, lower our overall storage cost, and enhance our disaster recovery environment,” says Jimmy Hu, Ameren’s infrastructure specialist. “To accomplish our goal, we needed to make a non-disruptive move of 10TB of data, encompassing more than 2,000 volumes of storage, while maintaining existing replications of data. In addition, Ameren had to maintain the existing Recovery Point Objective [RPO] of three hours during the migration process, which further complicated the effort.”
The difficult, time-consuming task of locating and testing solutions to help perform the migration task soon began.
“We knew that the standard system and storage vendor utilities could not meet our somewhat complex requirements,” says Hu. “So, we had to look for innovative solutions that did meet our requirements. The first product we initially reviewed looked like it could perform the tasks we needed. However, upon testing the product, we found it to be too limiting. Ameren has been an FDR, ABR, and FDRINSTANT customer for decades. So, we decided to bring FDRPAS in for a trial.”
FDRPAS, from Innovation Data Processing, was introduced in 2001 to ease data migration from older to newer disks. The product can move individual disk volumes or an entire disk controller to new storage devices without disrupting workload processing. Furthermore, FDRPAS can simultaneously swap shared disks on all sharing systems. When the FDRPAS swap of a volume is complete, the volume resides completely on the new device, and the original device is no longer required. If all the volumes on an old disk subsystem are moved to new locations with FDRPAS, the old DASD subsystem can be erased, powered off, and disconnected. To date, more than 1,400 installations have used FDRPAS.
Migration of data from old to new disk hardware can be costly and time-consuming. Without the use of FDRPAS, implementation of new disk subsystems might require that many applications, or perhaps an entire system, be shut down while volumes are backed up and restored to new locations. The conversion process may take many hours, even days, and often needs to be done during evenings or weekends; the conversion often gets delayed since the business requirement at most companies is for non-stop availability.
Ameren’s testing of FDRPAS soon began.
“The ability to create a point-in-time backup was important to us in case we needed to fall back to the source volumes, or if there was a problem with the target volumes, which impacted the replicated copies,” says Hu. “FDRPAS has a SWAPDUMP feature that makes it possible to create a point-in-time backup, but we needed to know if we had the resources to support this feature. Innovation analyzed the systems requirements and determined we had more than adequate resources to support the SWAPDUMP.”
