Summary

After importing your Trello projects to JIRA, any card attachments linked in Trello are not supported in JIRA and appears as a broken link.

Steps to Reproduce

1. In Trello, attach a card to an existing card as an attachment.
2. In JIRA settings, import your Trello projects to your JIRA's tenant using the External System Import tool.

Expected Results

All of your project, issues and card should be imported to your JIRA tenant.

''1 projects and 3 issues imported successfully!''

Actual Results

The attachment is imported to JIRA as an unsupported URL in the issue.

Below is the error is given in the import detailed log:

2017-12-22 08:24:37,536 WARN - Could not download attachment "http://xxxxcloudtest.atlassian.net/browse/TEST-24" for issue "abc": Could not create file.

Workaround

Manually link the card to your JIRA project using Jira Power-up in Trello.

To do this you must link your JIRA account in the Power-Ups of your Trello.