Inside Defence's mammoth data centre migration

Australia’s Department of Defence is nearing the finish line of a massive data centre migration project involving 150 enterprise applications across a range of mainframe, mid-range and x86-based systems.

The three-year migration project involved some 200 staff at its peak in mid-November and is considered one of the largest of its kind attempted in Australia.

Defence has opted to consolidate hundreds of data centres as part of the Defence 2030 vision, which aims to save the Australian Government some $1.9 billion.

One of the major projects within this wider transformation was the migration of applications from a Defence data centre housed within an ageing Telstra exchange in Canberra to a state-of-the-art cage within Sydney’s Global Switch data centre.

The Canberra facility had aged to the point in which its environmentals and electricals could not be upgraded to host new workloads.

Since late 2010, Defence has gradually built a raised floor, power, cabling and racking within the concrete shell in leases at Sydney’s Global Switch.

The department In late 2011 purchased a new set of servers, storage systems and networking equipment ready to host its applications. 

Defence has now migrated 150 applications onto this infrastructure - which represents around 97 percent of the project - the largest shift being in mid-late November under ‘Migration Group II’.

During one intensive 72-hour period, Defence and its industry partners shifted the majority of its mainframe and x86 applications over the network in one fell swoop.

“This was a significant piece of work,” said Daniel McCabe, assistant secretary of infrastructure architecture at Defence.

"It came after four major dress rehearsals to make sure changes were well-scripted and well-rehearsed.”

The migration was complex due to interdependencies between systems running across mainframes and x86 systems.

“A lot of our major business systems – from HR to finance and logistics systems managing  Defence’s inventory - are cross-platform,” McCabe said.

“For some applications, front-end web services might run on x86, the back-end database might run on mainframe.”

McCabe said the majority of effort within that 72-hour window was not on the migration itself (which involved moving applications over the network and the synchronising of databases) - but the testing of applications to ensure the migration didn’t hit any create any data or business process errors.

Defence conducted an exhaustive Business Validation Testing process to make sure the data stored and the business logic of the applications running on the new hardware in Sydney mirrored snapshots taken prior to the move.

With Migration II completed, Defence’s major applications are now running on brand new hardware in a modern data centre - but for two small web-facing apps.

Defence chose to postpone the migration of CadetNet and the wider public Defence web site in order to minimise disruptions to late-2012 announcements from the Minister’s office and Defence’s annual graduate drive. The two applications are expected to be migrated relatively easily this month.

Defence is now retiring infrastructure at the Canberra facility - re-deploying any current generation hardware to its disaster recovery facility in Melbourne, returning leased mainframe hardware to IBM and destroying disks.

The department did not use the opportunity to re-host applications or simplify its architecture, with the migration project being complex enough on its own.

But McCabe said Defence had designed the power, racking and cabling of its new facility “with a ten-year minimum view”, so it would not have to revisit power and comms concerns should it be required to modernise.

“We now have capacity to build out new requirements for our business,” he said.

The migration also has improved the department’s DR capability. McCabe said the introduction of SAN replication between Global Switch and its Melbourne facility has reduced recovery times by 80 percent. 

Defence’s data centre migration project will be explored in greater detail at the iTnews Data Centre Strategy Summit at the Royal Pines on the Gold Coast on February 11-13.