Integrating legacy systems into the cloud is not necessarily different or more challenging than moving any other application off-premises, cloud providers say.
One way to do it is to treat the cloud data center as if it were part of your IT infrastructure; it's technically feasible and is the quickest and easiest way, John Treadway, senior vice president at Cloud Technology Partners, said. "A cloud data center is just another one of my data centers. I don't have to do [legacy integration] differently, as a rule."
Another option is to migrate the legacy system to the cloud and then extend hosted virtual desktops to the user community, David Graffia, vice president of sales at dinCloud, said. "This allows for speed to market, greater security, business continuity/disaster recovery and BYOD. Also, since the application and desktop are residing in close proximity to each other, performance is greatly enhanced."
Another approach is to simply publish the application and allow users to connect back to it via a session, he added.
Integrating legacy systems: Main considerations
Latency is a key concern when integrating apps across a hybrid cloud environment. It's critical to make sure there is the right level of performance between apps, Treadway said. From a technical perspective, companies also need to ensure they have the right connection model to facilitate the integration of legacy systems.
Connectivity to the cloud has to have the right type of performance and security and be manageable, he added. Companies should ensure they have visibility and can see that systems are talking to one another and that the connection is reliably maintained.
"Can I construct the right path; ... is it secure; can I manage and monitor the apps; and how do I know the data between two systems is, in fact, the right data?" he asked. "Any kind of systems integration is complex, and they all have same issues: Is the Internet fast enough, secure enough and does it provide me with the right data? These things are not new to cloud."
However, transitioning systems to the cloud requires that additional work be done because "the network environment and integration and everything you're doing is just a little bit different to make you want to stop and think about it when you're doing it," Treadway said.
Brett Gillettcloud practice lead, Softchoice
Most often, when enterprises choose Amazon Web Services (AWS), they will opt to go with Amazon's Direct Connect, which involves provisioning a dedicated circuit from their on-premises data center directly to AWS using a third-party data center hosting company like Equinix, for example, Treadway said.
So the first step is to get the connectivity in place, he emphasized. "In the enterprise world, you don't want to do that over the public Internet because you can't control performance and there may be security issues."
But even with a dedicated circuit there can be complexity in the connection process and in how a company monitors and manage their cloud environment, "so you want to make sure you have the right tools and people in place to do that," Treadway said.
Connecting these networks together can be challenging, Graffia agreed. At dinCloud, the company addresses this through automation, starting with setting up an IPsec virtual private network (VPN) tunnel, then provisioning resources via a hosted virtual server, which can then be promoted to a read-only domain controller (RODC).
"This allows our clients to simply manage their existing group policies and streamline the application deployment," Graffia said. "We have also automated the synchronization of Active Directory, which enables our clients to add hundreds of users to the domain at once."
Integration of legacy systems to the cloud: How to do it right
Different approaches are used in the migration and integration of legacy systems and apps in the cloud, depending on the customer setup and requirements, Graffia noted. Some things he suggested companies should think about include:
- Replication tools can be used to simply replicate the application and data to the cloud. Once replication is done, services can be turned up in the cloud. This approach has a number of advantages, including minimal downtime and ease of migration.
- Physical to virtual (P2V) conversion can be done if customer applications are not virtualized before being migrated to the cloud.
- For applications with small data size, migration can be done over the wire.
- For applications with large data size, physical media can be used to seed the data to the cloud.
- VPNs are set up to connect to the cloud network, which is great when integrating legacy system apps with cloud.
"Before making any decisions, companies need to have a clear understanding of how their applications are being used right now," Brett Gillett, cloud practice lead at Softchoice, added. The best way to do this is through an in-depth application audit. Companies also need to understand the implications of moving to the cloud, from a cost and support perspective.
"If a company decides to go down the hybrid path, they need to ensure that connectivity between their on-premises and cloud-based infrastructure is reliable and provides a low-latency connection," he advised. "If either one of these requirements are not, the customer experience will suffer."
"If you're a provider, make sure you have a mechanism for your clients to use to create a secure connection like Amazon's Direct Connect," Treadway said. Also, make sure the right tools are in place, so the new system will run and perform at the level the customer needs it to.
"The better your tools and cloud provider to operate and govern and manage this, the more likely your clients will be happy and comfortable with your offering," Treadway said.
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