Time to Move On

Like the ABC, and also after 20 years of mainframe computing, the Seven Network had reduced TCO and enhanced flexibility as major drivers when it last year switched off the last mainframe used to control its network television system.

Project manager David Checkley says the Seven Network Television System application had not outlived its usefulness, and was in fact a key component of Seven's IT systems. However, towards the end of the outsourcing agreement that had hosted and managed this system, Checkley says Seven decided to migrate the application from the outsourced mainframe to an in-house Unix platform in order to lower costs and to position the company to be able to quickly address future broadcasting requirements.

"We maintained an inventory of the components of the application, which were all migrated. There was never any thought of legacy or non-legacy. Either the application was necessary for the company's requirements or not. Once that decision was made we just got on with the job of migration," he says.

Checkley says the Seven Network built on a small team for the migration and subsequent in-house support. "Seven migrated its Network Television System in eight months," he says. "Because we were insourcing, part of the planning was to ensure new staff came on board early, in order to have sufficient knowledge of the application before they were required to support it."

Repetitive test migrations, as well as checking the integrity of the migration, gave Seven accurate migration timings as well as the confidence that things would work in the production implementation, he says.

No Time for Downtime

When performing system, application or data migrations, IT managers often realize very quickly that bridging the gap between the old and new is going to present some challenges. And in this day and age, system outages are unacceptable, says Tim Rathbun, executive vice president, marketing and product management for GoldenGate Software.

"For example, one of our customers urgently needed to upgrade to an Oracle-based supply chain system. They are a $1.2 billion consumer health-care business. After running the numbers, they realized that if there was an outage and their production capability went offline, they would lose about $47,000 a minute."

The key, Rathbun says, is to manage the cutover in a way that minimizes or, even better, eliminates downtime. He says organizations must keep production databases completely accessible during the migration. This allows production systems to continue to run, ensuring that there is no loss in business opportunity and resulting revenue, regardless of the size or number of databases to be migrated. He says a contingency plan should be an integral part of any migration.

"Should you encounter any issues, it is absolutely essential that you have the ability to immediately revert back to the old system to enable your business to continue to function," he says. "However, it is absolutely essential that both databases are synchronized bi-directionally in real time. If this is not the case, even if your migration tools enable you to revert back to the old system in a timely manner, the data processed against the new database will not be reflected in the old database."

Rathbun says this resulting inconsistency could prove costly, with inaccurate data conceivably preventing a successful fallback to the old system.

An organization's best chance of minimizing legacy migration risks is in avoiding risks like these.