How to get the Trello External System Import configured and working?

[Ahmed Dajani]

I followed the steps in the documentation provided here, https://confluence.atlassian.com/adminjiracloud/importing-data-from-trello-951386555.html.  However, every time I click Next from Trello Setup page to be redirected to Trello so that I can authorize the data import.  I receive: There was a problem while creating a connection to the remote service.

Looking at the log, the only thing I can find is the following line: 

/secure/admin/TrelloSetupPage!default.jspa [c.a.j.p.i.trello.agileutils.BoardManagerAccessorImpl] The necessary JIRA Agile class is unavailable.

What configuration am I missing?

[Ahmed Dajani · Accepted solution]

Please disregard.  Trello was being blocked.

[Przemysław Mazur]

Hello Ahmed, you could tell where it was blocked?

[Przemysław Mazur]

@Ahmed Dajani 

[Ahmed Dajani]

The server was being blocked from any traffic going out to the internet.  Once our server team allowed for the traffic to go through, the import worked.