Hi Pauline,
Some more background on my setup. So for some time now I have been using an open source file synchronization program SyncThing, maybe you're familiar with it, to sync my address book between my viewer computers. I know this is probably an improper way of doing this, but as it is only myself using the viewer computers, and as long as I can remember to close the viewer before I switch to another viewer computer, nothing has gone wrong doing it this way so far. Now that the Linux viewer has remote address book sync via self hosted server I thought I should finally start to use this feature and abandon the Syncthing method, which I think I have been using for about 2 or 3 years now with no major issues except it can create a sync conflict if I forget to close one viewer and open the viewer on another computer as they are all using the same address book xml file, which isn't a big problem since it's just me, but even sometimes I forget, and that could be a big problem that is avoidable if I can get this to work on the server side.
So, my method for populating the cloud address book was this:
On the self hosted server I created the users (one for each viewer pc) and the address book.
On one of the viewer PC's I made a copy of the address book .xml file I've been using, I believe this .xml file is the output of using the address book backup feature on the Windows Viewer; I no longer use the Windows Viewer.
Using the copied .xml file, I added it as a second address book in the viewer PC.
Then I used the sign in button to log in to the self hosted server with the viewer pc and added the new cloud address book to the viewer, now at this point this viewer has two local copies of the same address book and one empty cloud address book. The second copy of the address book was for me to figure out how to transfer that to the cloud address book without possibly ruining the original data, (which I'm glad I did because all of the Internet ID's were lost in the data transferred to the cloud address book.)
Then I created folders within the copied address book and put all the contacts into folders and dragged and dropped the folders into the cloud address book. This worked, except for the Internet ID and server DDNS data is having an issue that we've been trying to figure out. I have quite a few contacts and if possible I would really like not to have to enter them all in on the server side, but I noticed when I did just one it seemed to keep the Internet ID and server data when I entered it on the server side, so it appears there is a problem using the cloud enabled viewer to write to the server address book. Also of note, any edits made to a contact on the cloud address book from the viewer results in the Internet ID / server address being erased and Direct connection being chosen, essentially the Viewer PC acting on the contact seems to corrupt the data somehow. My guess is it's probably a malfunction on the server computer. This isn't mission critical to me that it be solved immediately, this is just very interesting and I'd like to solve it eventually, and it will be useful once solved. Any help or input is greatly appreciated.