So, I wanted to chime in here because I had the same issue, and solved it. This was near the top of my google search, so hopefully it helps somebody else. The resolution was to manually sync the configurations, then once synced, perform the automatic synch, which succeeded. To manually sync, go to Device->Setup->Operations, then "save a named configuration snapshot". Open it in a text editor. There will be some basic information that you need to edit manually: management address and HA IPs and peer IPs, and hostname. It will help to make a note of all of this information beforehand, and then search the document by the IPs you are looking to edit. Other than that, everything can be overwritten. Once the edits have been made, jump on the backup FW to the same screen, and Import named configuration snapshot. Then Load named configuration snapshot and commit. Once committed, you can go back to the primary FW and force the auto-synch. Hope this helped somebody! Greg
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