Chapter 3. Upgrading to Red Hat Virtualization 4.1
3.1. Upgrade Considerations
- Upgrading Red Hat Virtualization Manager to version 4.1 can only be performed from version 4.0
- To upgrade the Manager from a version earlier than 4.0 to 4.1, you must sequentially upgrade to later versions of the Manager before upgrading to the latest version. In other words, the Manager upgrades must be stepped. For example, if you are using 3.6, you must upgrade to the next version (4.0) first. See Upgrading to Red Hat Virtualization 4.0 in the Upgrade Guide for Red Hat Virtualization 4.0 for instructions to upgrade 3.6 to 4.0.If you are using 4.0, you must update your installation to the latest 4.0 minor release, before upgrading to 4.1. See Updates between Minor Releases for instructions to update to the latest 4.0 minor version.The host upgrade procedure does not need to be stepped.
- Downgrading is not possible after changing the data center compatibility version to 4.1
- When you upgrade the data center compatibility version to 4.1, the data domain storage format changes from version 3 to version 4 and cannot be downgraded. Therefore, you cannot attach a data domain from a 4.1 data center to an older data center. However, you can attach a data domain from an older data center to a 4.1 data center, but the storage format will also be upgraded and cannot be reversed.