Migrating Gliffy diagrams from JIRA Server or Data Center to Cloud
Gliffy for JIRA is available for both JIRA Server and Cloud. Gliffy diagrams are stored as attachments to JIRA issues. If you migrate your JIRA instance from Server or Data Center to Cloud, your JIRA issues and associated Gliffy attachments will migrate to the new Cloud instance as long as you choose to migrate attachments, your source and target JIRA instances have the Gliffy for JIRA plugin installed and you use the JIRA Cloud Migration Assistant to perform the migration.
For detailed information about migrating, see the Confluence help: https://confluence.atlassian.com/cloud/use-the-jira-cloud-migration-assistant-to-migrate-from-server-to-cloud-993925215.html.
After the migration is complete, ensure that all JIRA issue attachments were migrated correctly during the process. Checking a few JIRA issues known to have attachments.
Important: If a diagram has more than one version (see Viewing the revision history), after the migration, only the latest version of the diagram will appear and its version will be reset to v1. All previous versions of the diagram will be saved as a separate zipped attachment file.