Overview
Azure and Jira have a different approaches to item hierarchy.
While Jira allows for a three-level hierarchy (Subtask → Standard Work Item → Epic), Azure does not restrict the number of hierarchy levels, allowing for unlimited Parent-Child relations in a single hierarchy tree.
Visual representation of Azure hierarchy depends on the chosen process and is up to 4 levels.
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When neither Epic nor Subtask synchronization is enabled, Multi-level-hierarchy synchronization section serves standard link synchronization only (with forced Parent/Child link on Azure side).
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Three-level Azure configuration (Basic Azure DevOps process)
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Configuration > Mappings > Types:
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Four level Azure configuration (Agile Azure DevOps process)
Configuration > Mappings > Types:
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Configuration > Mappings > Hierarchy:
(For custom link relates to)