Posted by: Beth Cohen
Cloud architectures, Cloud migration, enterprise cloud services, hybrid cloud, PaaS, server migration
Question: I am interested in moving some of my applications to the Cloud. How can I preserve my software investment while taking advantage of the efficiencies of the Cloud?
One of the many touted reasons for moving applications to the Cloud is to avoid vendor lock-in, so virtual environment independence is essential for any cloud migration. However, today all the cloud stacks available, EC2, Cloud.com, Terremark, etc., assume that anyone moving into the cloud is creating new servers, building new systems and applications, not migrating their existing application and systems to the cloud. Yet, many companies interested in cloud migration do not want to incur the costs associated with application level porting of their existing IT investment. As many companies have discovered, migrating physical or virtual servers and applications directly to the Cloud is not as simple as it might seem on the surface.
The good news is that there are a number of good ways to address this issue. Which one is the right one for your company is going to be dependent on your specific requirements. However the basic choices are a full migration of the existing set of systems to a PaaS (Platform as a Service), moving some of the systems to the cloud to create a hybrid environment, or creating a virtual data center in the cloud. In more complex environments, a mix of the different approaches might be the right answer.
Full migration – This is the approach you would choose if you need to preserve as much of the existing systems as you can. While you will need to change the IP addressing schemes and not all platforms are supported, this can be a very cost effective method. The downside is that each cloud environment is somewhat different, so migrations require tools need to have flexibility and are aware of the specific environment. The number of migration tool products or applications available on the market is surprisingly small. Once you ignore the specialized migration tools written by the virtualization platform vendors (VMware vCenter Converter and Citrix XenConvert for example), which are obviously not going to work in a cloud environment, and the repurposed backup tools (Acronis Backup and Recovery v10 Advanced Server Virtual Edition and Double-Take Move for example), the number of tools that have automation and multi-platform support is limited to two. The RiverMeadow Networks ShamanTM Appliance and PlateSpin Migrate are the only two products on the market today that are both automatable and support virtualization platforms other than Hyper-V and VMware.
Virtual data center in the Cloud – Another product on the market, Cloudswitch takes a different approach to complex existing data center environments. CloudSwitch encapsulates the VM and preserves all of the existing network architecture/topology, including the IP addressing schemes. The CloudSwitch solution can be very elegant for companies that are not ready to give up on their existing data center infrastructure but want the capability for transparent cloud bursting. They also offer a great solution for companies that have reason to keep their networks completely private, yet still move their workloads into the Cloud. Be aware that since the solution adds another layer of abstraction there is some extra overhead. Of course, the issue of network capacity and the ability to move large data sets across the WAN remains.
Cloud bursting and hybrid environments – For companies that want to use the cloud for augmentation of their existing services the option of taking a portfolio approach to service locations might be the right solution. The issue with this approach is the potential for incompatibility between the different environments and the limited management tools. VMware recently announced Cloud Connector, a new tool to manage hybrid environments across venders, but it does require that all the environments be based on the ESX virtualization platform.
Ultimately which migration approach works best is going to be governed more by the existing environment, the business objectives and the limited number of tools to do it right. As the Enterprise Public Cloud matures, the tools for migration will become more available and better matches to the needs of businesses.
About the Author
Beth Cohen, Cloud Technology Partners, Inc. Moving companies’ IT services into the cloud the right way, the first time!