h2. Migration background

The BMC Topology Discovery and Foundation Discovery products (later renamed to BMC Atrium Discovery and Dependency Mapping, or BMC Atrium Discovery) were recently replaced by the Tideway Foundation product that BMC acquired in October 2009. Immediately upon acquisition, BMC started shipping the Tideway product as BMC Atrium Discovery version 8.0. Going forward, BMC recommends that all existing users migrate to version 8.2 from their installations of earlier versions of the product.

{note:title=For users of Tideway Foundation}
If you are using a version of Tideway Foundation prior to version 8.0, you do not need to migrate your installation. You simply need to upgrade to the latest version of BMC Atrium Discovery. See [Upgrading to Version 8.2] for more information. Migration is only required from the BMC Discovery products released before the BMC Software acquisition of Tideway.
{note}

Clearly, versions 8 and later contain a different product architecture from versions 7.5 (and its predecessors). Data discovered by these products and synchronized to BMC Atrium CMDB is going to be very different as a result. Two illustrative examples include:
* Version 7.5 populates a list of products for a host based on the list of installed packages, whereas version 8.2 populates the list of products based on the products it finds running. As a result, the lists are very different, often with little overlap.
* Version 7.5 provides a number of CMDB extensions to create classes that it then populates (for example, for J2EE and SAP data). Version 8 uses the out-of-box CMDB model for these items, and therefore creates different CIs in the CMDB.

h3. Discovery configuration
Your discovery configuration for BMC Atrium version 7.5 likely contains valuable information that you want to carry over to your version 8.2 implementation. The configured credentials, discovery jobs, and UAD signatures took time to build and should be taken advantage of in the new version. The following pages describe how to migrate these items to the latest version of BMC Atrium Discovery:
* [Migrating credentials]
* [Migrating UAD signatures]
* [Migrating scheduled discovery tasks]

{note:title=Note}
The supported migration path for BMC Atrium Discovery is from version 7.5.01.03 to version 8.2. If you plan to migrate data from earlier versions of BMC Atrium Discovery (or BMC Topology Discovery and BMC Foundation Discovery), you must first upgrade to version 7.5.01.03. For users migrating their mainframe data using BMC Discovery for zOS version 1.5, you must first upgrade to version 1.6.{note}

h3. CMDB data and ITSM consuming applications
While many of the CMDB classes populated by these two product versions are not reconcilable, the {{BMC_ComputerSystem}}, {{BMC_LanEndpoint}}, and {{BMC_IPEndPoint}} classes _will_, in almost all cases, reconcile correctly. This enables a migration approach for BMC Atrium CMDB that retains all the history of computer system CIs, although any essential data attached to CIs that make up a computer systems will need to be handled specially.

The broad approach is that all CIs in BMC Atrium CMDB that will not be reconciled correctly (that is, the items that make up a computer system: software servers, CPU CIs, and so forth) and that are not involved in IT Service Management (ITSM) items such as incidents and changes, will be deleted. BMC Atrium CMDB will be repopulated by the BMC Atrium Discovery 8.2 [migration utility|Using the migration utility#migration utility|link tip], and these new items will continue to be used by BMC Atrium CMDB consumers to handle ITSM applications. See [Migrating a CMDB populated with ADDM 7.5 to ADDM 8] for more information.

h3. Service impact models
BMC Atrium Discovery 8.2 exports impact relationships between all Service Impact Manager (SIM)-enabled classes in the same way that version 7.5 does. Any impact relationships that you manually create between CIs populated by version 7.5 must be rebuilt between the corresponding version 8.2 CIs. See [Migrating impact models] for more information.

Similar to the ITSM use case, all CIs in BMC Atrium CMDB that are not involved in creating service models will be deleted. BMC Atrium CMDB will be repopulated by the BMC Atrium Discovery 8.2 [migration utility|Using the migration utility#migration utility|link tip], and these new items will continue to be used by BMC Atrium CMDB consumers to build service models.

h3. Impact on users
It is important to understand that users are going to see significant changes to the data that they work with. Some data will appear differently, and some items will show up in different CMDB classes.

BMC recommends that you first migrate your development CMDB environment, both to validate the migration approach in your organisation, and to familiarize yourself with the changes that happen to the data in your CMDB. It is important that you educate your users about the changes that they should expect in order to keep them productive immediately after the migration. The migration solutions detailed in the following sections follow this methodology: check the impact on your environment, test, migrate the data, and then validate.

{tip:title=Best Practice}After you have determined that you are ready to migrate the data, perform the migration promptly to avoid implications of introducing additional data into the CMDB, thereby changing your original test results and causing confusion because of inconsistent data.{tip}