Scenario

 

You need to synchronize with a Jira Cloud instance, and your instance is on a private network, not accessible from the internet.
So a Connection from the Exalate for JIRA Cloud to the private server is not possible.

Solution

  1. A possible solution is to enable public-private synchronization as this is fully supported. 
    In this configuration, all connections are initiated from the private server.
    Following guide provides the details: Setup your first synchronization between Private JIRA Server and Public JIRA Cloud.

  2. Alternatively, you can whitelist 2 servers
    • The Exalate mapper URL: connect.exalate.net
    • The Exalate application itself.  The URL is located in General settings of the Exalate admin menu on your JIRA Cloud node.