Why do you need to get a new domain? you can reuse the old one surely.?
Can't you export the data, keep the old media directories, and import it all into a new install?
I've only just updated to 4.2.x because of my worry of trying to upgrade ruby, which wasn't a smooth process, and I've probably got 3 damn copies of ruby in different parts of my filesystem, but apart from that, it was a smooth upgrade after that fiasco.
Yes sadly.
I bet in future there will be a way of being able to search other instances to find posts by yourself on peoples' accounts that followed you, as some of it will be cached, but it would take a long time and a lot of network traffic I expect, and depending on other servers' media retention policies, you might not get all your attachments either.
I have been running Owncloud since 2011 without any reverse proxy and it's been fine.
I'm still on an old version because every time I have tried to upgrade it, it has fucked up, and i've wasted loads of time getting it back running again. New versions /should/ be better I hope!
Pick decent user passwords, protect it with SSL, and have a local firewall on your server that only allows required ports though (80 and 443), and you should be fine.
I take a backup of mine now and again, but it's quite small - only about 50gb.
Nextcloud is more like a "star" configuration, where Nextcloud is the server, with multiple clients. Of course the clients can cache data from Nextcloud.
Syncthing is more like a mesh, where each client serves data to others (although this is configurable),
Nextcloud has way more features, like shared calendars, video conferencing plugins etc, which is great, but may be overkill for your needs.
I use both, although NextCloud/OwnCloud fits my needs better.
I would say syncthing is easier to set up. There is more admin overheard (esp upgrades) with NextCloud/OwnCloud.
If the domain isn't critical if it changes, you could use freedns.afraid.org.
I've been using the free version for over a decade (but did donate recently). A couple of domains have come and gone, so I've had to pick new ones, but it's not a big deal.
Content warning: eye contact
The technical reason is the nginx service is expecting a domain name so it can route it to the right webserver.
You can use nginx to host multiple domains that get sent to different web servers.
For example, i have a
pixelfed.mydomainand amastodon.mydomainconfigured in nginx, which are both hosted on the same server.If you're just using an IP address, it won't know where to forward your requests too.
There might be a "default" config you could use, or maybe you could use an IP in the
server_nameoption, but it would be less confusing to just get a temporary domain as u/fruey suggests.