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All you need to do to migrate from Server/Data Center to Cloud is to create the Issue Matrix custom fields as Issue Matrices(panels) in your projects' configurations on the Cloud. There is no automated way of doing it for now, but configuring Issue Matrix for Jira Cloud is a super-fast, easy, and intuitive process. You can learn more about how to configure and use Issue Matrix for Jira Cloud in our documentation.
The significant difference between the server and cloud apps is how you do the configuration. On Jira Server, after installation, you need to create custom fields of Issue Matrix type. Once you are ready with the configuration, these custom fields appear as tables in your issues when you are viewing them in Jira.
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The migration requires creating Issue Matrices corresponding to the Issue Matrix custom fields on the server. To achieve it, you can use the project linking feature in the cloud app.
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