Exposing a local HTTP server to my application

Questions / Help
1

I am trying to prepopulate a volume with some files, but all my attempts until now have failed:

  1. Connecting through SFTP from Windows (with or without WSL). This seems to be a known issue.
  2. Using rsync from a VM running the latest Ubuntu 22.04. Used fly ssh issue --agent, followed by fly proxy 8080:22, followed by rsync --rsh='ssh -p8080' foo root@localhost:/data/foo. Rsync fails with the message: rsync error: protocol incompatibility (code 2) at compat.c(600)

Now I am looking for a workaround and I thought it might be possible to spin up a local web server and serve the files I want to transfer, then use curl from a shell in my application (through fly ssh console) to download them. Is it possible to connect from the application to my local machine and access its webserver? If so, how?

2

I’ve installed an SSH agent into the server, had it listen on port 2222, and then set port 22 in services as an exposed port (the internal port is 2222). Then I was able to SSH in via normal SSH (use scp, etc).

Port 22 is already taken on some internal networks by a process in fly to support the fly ssh command IIRC.

3

I ended up trying scp with the proxy approach mentioned in my original post (instead of rsync) and it worked. I did have to install it first on the server, though. This definitely feels like a less polished side of fly.io, in contrast to the rest of the experience, which is usually great.

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