To migrate DNS to the new platform, you can use tools like iManager or the Java Management Console. During migration, the configuration details as well as the data are migrated to the destination platform.
In this scenario, both the NetWare server and the OES 2 Linux server are on the same eDirectory tree.
In this scenario, the Netware server and the OES 2 Linux server are on different eDirectory trees, so the migration is across the trees.
Depending on your setup, you can choose to migrate a single server at a time or migrate all the servers at the same time.