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If you have Xray installed in a standard Jira server, you can just update it as detailed in the FAQ Installation. Make sure to check the Jira compatibility matrix first.

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Both can be achieved in Xray's administration (see FAQ for Quick Setup for instructions), although the first one may also be done in the project settings page.

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Please refer to Test Versioning.

How do I define which

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Tests should be used for regression testing?

Please take a look at FAQTips for organizing tests.

Can I link Tests to other Tests?

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Yes. You can add one or more columns in your CSV and then map them to "Link Tests"'. Please see the documentation in FAQ Importing Manual Tests using Test Case Importer.

Can I migrate my Tests from one Jira server to another?

Yes, with some constraints. Please see the proper section within the documentation in FAQ Importing and Exporting Tests (CSV).

How can I migrate my legacy executions to Jira?

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One way is to use the REST API: FAQ. This ; this will require some development effort on your side and will also require that you have the Tests already created in Jira.
Another option is to use the built-in Jira CSV importer (not Xray's Test Case Importer) to create the Test Executions with the Tests. However, you would still need to use the REST API in order to submit the results for the Tests contained in those Test Executions.

Please see the proper section within the documentation in Importing and Exporting Tests (CSV).

Integrations

Can I trigger/start Jenkins/Bamboo builds from Xray?

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