RackSpace cloud resizing (Scaling) steps

Step 1: Resize request is queued
The resize request will be processed as resources permit. The queued period is usually quick, but can vary depending on other host machine activities.
Step 2: Initial preparation of new server
This is the longest part of the upgrade, during this step the original server remains up and running.
Step 3: Current server is shut down and migrated
You will experience a downtime varying in proportion to fullness of the filesystem.
Step 4: Verification of new server
Your newly resized server should now be available. Login to verify that the server is intact and functioning as expected. After verification, the old server will be purged from the system and your account will be billed a prorated amount. If no verification is made, the resize will be automatically verified after a period of 12 hours.