Easiest and most secure way? Mail (or hand deliver) a flash drive. That's how they transfer data between super computers and data centers. (AWS even has dedicated trucks to do it)

In one go? Look at Wormhole

But both ends must stay online until it is complete.

Could send it over ATP - Avian Transfer Protocol.

Does require a USB stick and for your friend to train a pigeon though.

I would use syncthing for this

I use Syncthing for this things, you can even set a folder and keep it in sync with multiple users because it uses P2P

I tried creating my own torrent and was able to dl it on another device, but on her machine it stayed at 0% and wouldn’t let me connect to seed

At least one of the torrent clients needs to be fully connectable (port forwarded) for torrents to transfer data. You need to test that e.g. test your torrent client's incoming connection port with a port test website like https://www.canyouseeme.org, https://www.yougetsignal.com/tools/open-ports, etc. & make sure those port test websites can successfully test connect to your torrent client's incoming connection port. If the test fails then you need to look at opening the port via your OS firewall and/or router firewall.

Is FTP a good option? I set up a proxmox server last night but I don’t really know what I’m doing yet

Probably best to avoid FTP if you don't know what you're doing, it's not all that secure.. you'd want to at least configure SFTP or FTPS which is just going to be more complicated vs fixing your torrent issues. And technically you still need to make those connectable (port forwarded) too, just like your torrent client.

All that aside it's probably easier to use Syncthing if you can't get the torrent working.

You could also try one of those file transfer websites that use WebRTC to transfer data peer to peer e.g. https://file.pizza or similar. Not sure how well they work for huge amounts of data but their github page mentions that Firefox is better for that, apparently Chrome starts to choke with data 500+ MB.

Don't put FTP on the Internet if you don't know how to secure it.

If you're relatively nearby, you could just use a flash drive. Or mail one. If not, the other comments have good suggestions.

yep, id use sftp. my mail provider (proton) also gives me like 500gb in a 'drive' which is great for transfers like this

Btw: Might be that you're behind a NAT (router) and that's why bittorrent doesn't connect. You'd need to figure out which port your torrent client is configured to listen on and then do "port forwarding" of that port to your machine in the router you got from your ISP. Or use something like UPnP that does this automatically.

Not sure if that applies in your case and it's unsolicited advice... But a fairly common issue with bittorrent.

Syncthing

I would use Resilio Sync. It uses bittorrent under the hood. https://www.resilio.com/individuals/

maybe SimpleHTTPServer (python) on the host and curl -C on the other machine?

Magic Wormhole protocol. There's a lot of clients out there. Here's some:

• https://github.com/magic-wormhole/magic-wormhole
• https://github.com/schollz/croc
• https://github.com/magic-wormhole/magic-wormhole.rs

There are website services where you both stay online and transfer directly.

There could be direct peer to peer transfer tools that are more robust.

If you want to go through a file transfer/hoster

• no limit https://gofile.io/
• 300 GB limit https://1fichier.com/

There's some more, those are the top two in my bookmarks.

You'd do good of encrypting/7z-passwording if you don't want others to see the content, just to make sure not to have to trust the hoster.

Create a multi-part archive (...probably about 250 parts...) with a strong password, upload each part to whatever the current equivalent to Megaupload is, and let them download it at their leisure.

With no accounts on either end, should only take about three months for each to be complete.

Alternatively, you could put it on a thumb drive and drive it over if they live fairly close.

Torrent.

My lazy way is NGINX with autoindex.

If it's to go over untrusted network (e.g.: internet, school network) I use SSH for port forwarding. Lazy encryption.

Something like this works just fine:

worker_processes 1;
daemon off;
events {
}
http {
        default_type application/octet-stream;
        server {
                root /storage/emulated/0/sharedfile;
                listen 127.0.0.1:30000;
                location / {
                      autoindex on;
                }
        }

}

sharedfile is a directory with the files.
On remote machine if I am not mistaken

ssh -L 127.0.0.1:8080:127.0.0.1:30000 username@host

Then just access it in web browser on 127.0.0.1:8080 or whatever port you chose.
In PuTTY you can find this under "Tunnels".

Of course, you need to have SSH server set up as well.

Toffeeshare is pretty good for this kind of thing. I don't think there is a size limit, only restriction is that it must be only one file so you must create an archive to send. But no install, no configuration to do, it's one of the simplest way to send a file IMO

Edit: typo

Swiss Transfer

I think file.pizza might be a good solution

Sounds like connectivity issues. Can you guys manually add the other's IP address? Do you have DHT/PEX enabled?

rsync can resume partial transfers, but you really should break that file up. Trying to do it in one go is crazy.

Maybe check out Tailscale. It's mainly a mesh VPN for your own devices, but they have a lot of options included so you can share stuff with other people.

croc is a good solution for this if true P2P stuff fails

Just to throw another option into the mix:

Maybe create a VPN connection with wireguard, then you can just transfer them however you'd do it in a local network? Tailscale would be an easy solution to achieve this.

Is it a single 50 gig file ? If not telegram has decent speed and can handle 2 gig files pretty well .

OnionShare?