Cross site connections
You can setup connection between 2 Jira sites to facilitate project migration, Jira configurations clone, restored Jira issues
To connect two different sites, Revyz - Data Manager for Jira | BYOS app should be installed in both the sites to make a connection and also region should be same both the sides.
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Click on add connection
Enter connection name
Enter site url
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Click on Generate connection token
Copy that token
Open destination site & click on setting in left navbar - > activate connection
Paste connection token & click on Activate