Next-Generation Cloud Migration Considerations and Options
Our Next Generation Cloud Servers powered by OpenStack® offer an open, flexible cloud platform. With a responsive API and an improved Cloud Control Panel it's easier than ever to manage your server instances.
If you're considering moving your application from our First Generation Cloud platform to our next generation cloud servers, weigh the pros and cons of the new platform before committing to a cloud migration. While we're excited about the possibilities a next generation cloud servers offers, the differences between the environments might make our First Generation Cloud a better choice for your application.
Our Next Generation Cloud platform offers some benefits over the original.
The OpenStack API used by our Next Generation cloud is responsive and flexible, with room to grow. New features include management of server metadata.
Next Generation Cloud Servers have assigned IPv6 addresses, though at this time we only support one assigned IPv6 address per server.
You can choose the region that will house a created cloud server in our Next Generation cloud environment.
Regional control helps you manage back-end availability between your servers and connectivity to services such as Cloud Databases and Cloud Load Balancers. You can also ensure that you have copies of your application in multiple regions to aid with disaster recovery.
Disk management is more flexible and with it you can repartition your Cloud Server's virtual disk and switch file systems if desired.
The Next Generation cloud's OpenStack underpinnings provide the potential for interoperability with OpenStack-based tools like python-novaclient, as well as compatibility with private and third-party clouds running OpenStack.
General Purpose and I/O Servers
Our Next Generation platform includes General Purpose Servers as a server creation option. General Purpose Servers offer dramatic improvements over Standard servers in disk and network speed. For more information, see our article, What Is New with General Purpose Cloud Servers.
Before committing to a switch, be sure your application isn't dependent on a feature or option that isn't available in our Next Generation cloud.
Not all features of First Generation Cloud Servers are ready for our Next Generation environment. At this time, that includes the creation of shared IP groups via the API.
256 MB instances
Instances with 256 MB of memory are not available for Standard Cloud Servers - Standard server sizes start at 512 MB RAM.
IP address change
At this time all migration options involve moving data to a new server, and the new server will have a different IP address from the original instance. After a migration you will likely need to make DNS changes and application configuration changes to account for the new IP address.
Virtual CPU allocation
Our First Generation servers are less strict about allocating CPU time on the host to instances. If your application relies on frequent CPU bursts, you may see a reduction in performance on a Standard Cloud Server. Conversely, if you rely on consistent CPU power (without being affected by bursts from other instances on the host), next generation cloud servers are more reliable in that respect.
Note that in some cases our virtual cloud server packages can offer more virtual CPUs than our First Generation platform. See the Cloud Servers pricing page for more information on virtual cloud server vCPU allocation.
Switching an existing application from the First Generation Cloud to our next generation cloud requires the migration of your data to a new next generation instance. In addition to the change in IP address, finalizing the move to the new server may require some application downtime.
To help you migrate existing data to our next generation cloud, the Cloud Control Panel offers the ability to take a special snapshot of a First Generation Cloud Server that is automatically converted to a Next Generation snapshot. The new snapshot can be used to make a Next Generation Cloud Server.
Using a snapshot to migrate to the Next Generation cloud can be a simpler and quicker process than migrating your data with rsync, but it will not work with all instances. Support for snapshot migration is determined by the base image used to initially create the instance.
Manual migration is available as an alternative for unsupported instances and is described further along in this article.
To create a Next Generation snapshot from a First Generation server, go to the Cloud Control Panel and click the action gear for the server you want to duplicate, and select Create Image. If the server is compatible with the conversion process, you'll be offered a choice between making a First Generation or Next Generation image.
For a converted image choose the Next Generation Cloud Server image option. Once the snapshot creation is complete you'll see it as an image choice when creating a new Cloud Server. Note that snapshot storage pricing on Cloud Files applies.
If you don't see an option to create a Next Generation image, your instance may not be supported by the conversion process at this time. In that case you will use a manual migration approach as detailed in the next section.
If you have trouble creating the image please contact support and they will assist you.
Bear in mind that the IP address of an instance created from a snapshot will be different from the server used to create that snapshot. Depending on your application there may also be issues if both the original server and the new server are active simultaneously.
For instances that aren't supported by our snapshot-based migration process, or for users who prefer a more hands-on approach, we offer some articles describing how to manually migrate your data to a next generation server.
Remember to take the size of the original server into account, as well as other considerations like the region of connected Cloud Database instances and Cloud Load Balancers when creating a new server for a manual migration.
General Purpose and I/O Servers
Some additional factors apply when migrating to a General Purpose or I/O Cloud Server, like system disk size and configuration of any data disks. For advice specific to General Purpose and I/O Servers, see our article, Migrating to a General Purpose or I/O Server. Our article series on migrating a Linux server provides instructions for migrating your data via rsync, either with a manual process or with the assistance of a python script.
Web Farm Framework on Windows 2008
To migrate IIS and MSSQL data on Windows 2008, you can use Microsoft's Web Farm Framework per the instructions in this article.
Web Deploy on Windows 2012
To migrate IIS and MSSQL data on Windows 2012, you can use Microsoft's Web Deploy tool per the instructions in this Rackspace Community post.
After a migration
After migrating to a new Cloud Server remember to make any necessary changes to DNS information or load balancers for your application.
Also bear in mind that existing First Generation snapshots can't be used to create Next Generation servers. Don't forget to make back-up arrangements for the new server.
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