Install the newest version of the https://marketplace.atlassian.com/apps/1222010/jira-cloud-migration-assistant?hosting=datacenter&tab=overview
Enable the “migration dev mode” dark feature
1. Determine your Jira base URL in the system settings under “Base URL”
2. Navigate to <Jira_Base_URL>/secure/SiteDarkFeatures!default.jspa
3. Enter migration-assistant.app-migration.dev-mode into the input field
4. Click “Add” or “Submit”
5. (You can disable the feature after migrating by deleting the migration-assistant.app-migration.dev-mode key again)
Make sure to have have the newest version of Agile Hive on your Server / DC instance
1. you need at least version 3.64.3 to initiate a migration in general
2. version 3.72.1 enables the migration of more data, like e.g. custom fields
With version 4.1.0, Agile Hive for Data Center supports Epics on all levels. That means, that hierarchical links between issues from the same project are possible. As this is not yet possible in Agile Hive for Cloud, make sure to migrate Agile Hive Epics first. Follow this article here: https://info.seibert.group/display/AGILEHIVE/Cloud+Migration+Prerequisites

Migration execution

General migration guidelines / advice

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