Considerations for migrating to a General Purpose or I/O cloud server

General Purpose and I/O-optimized Cloud Servers offer an increase in
drive and networking speed, but there are some factors to consider before
moving your current environment. This article provides information
that you need to consider to ensure that you are ready to move.

Premigration considerations

Consider splitting your web and application servers from your database
server and putting them behind a load balancer. This split will enable
you to easily scale horizontally in the future without the need for
downtime or DNS changes.

Premigration actions

Migrating from "Standard" or "Classic" flavors

• An image from a Classic or Standard server can build a General Purpose server that is one size larger. For example, a 1 GB Standard server image can build a 2 GB General Purpose server. If your Standard or Classic server is 8 GB or larger, you can’t perform an image-based migration because of the larger disk allotment on the older flavors. If you have an older Linux server, you might be able to resize it down to 4 GB or smaller, and then create an image that will build a General Purpose server.

Migrating from "Performance" flavors

• Any Performance server image can build a General Purpose server. However, 2 GB and larger Performance servers have a data disk that is not captured when you image the server. Thus, you must copy the data from the data disks manually via rsync, Robocopy or some other method.
  

Understand how resizing works

• General Purpose servers can resize, but only up, and only to a maximum size of 8 GB RAM/160 GB system disk. Rather than resizing (scaling vertically), we recommend scaling horizontally (adding multiple cloud servers) which increases the fault tolerance of your application.

• Standard and Classic servers can resize up to 30 GB RAM/1.2 TB system disk.

Other considerations

• If you use Cloud Backup, ensure that all of your data is backed up on your current server, and test a restore.

• Before deleting the current server, build a test server from your image and verify that it boots correctly.