Devices cannot see each other over the internet?

[Giraffaman]

So far I've only been able to get devices to see each other if they are in the same subnet. As soon as I connect over the internet with or without VPN, my devices stop seeing each other.

This is what I've tried:

• pair devices - once connecting via the internet, both devices still show they're paired, but they do not see each other
• put devices in the same room - same behavior as with pairing
• use a VPN (wireguard) which puts my devices onto the same network, but on different subnets
• enable fallback to websockets

Pairdrop sits behind a reverse proxy (nginx proxy manager) but with no special config and Websockets are enabled:

This is the docker compose config I am using (basically just copied from the docs for testing):

version: "3"
services:
    pairdrop:
        image: "lscr.io/linuxserver/pairdrop:latest"
        container_name: pairdrop
        restart: unless-stopped
        environment:
          - PUID=1000 # UID to run the application as
          - PGID=1000 # GID to run the application as
          - WS_FALLBACK=false # Set to true to enable websocket fallback if the peer to peer WebRTC connection is not available to the client.
          - RATE_LIMIT=false # Set to true to limit clients to 1000 requests per 5 min.
          - RTC_CONFIG=false # Set to the path of a file that specifies the STUN/TURN servers.
          - DEBUG_MODE=true # Set to true to debug container and peer connections.
          - TZ=Etc/UTC # Time Zone
        ports:
          - "9476:3000" # Web UI
        networks:
          - bay-21-internal

networks:
  bay-21-internal:
    external: true
    name: bay-21-internal

Debug log:

• 10.0.0.55 is my docker host
• 41.66.99.34 is my phone over mobile connection
• 10.0.0.253 is my router
• first attempt was internet no VPN, second was with VPN, third was over Wifi no VPN

----DEBUGGING-PEER-IP-START----
remoteAddress: ::ffff:10.0.0.55
x-forwarded-for: 41.66.99.34
cf-connecting-ip: undefined
PairDrop uses: 41.66.99.34
IP is private: false
if IP is private, '127.0.0.1' is used instead
----DEBUGGING-PEER-IP-END----
----DEBUGGING-PEER-IP-START----
remoteAddress: ::ffff:10.0.0.55
x-forwarded-for: 10.0.0.253
cf-connecting-ip: undefined
PairDrop uses: 10.0.0.253
IP is private: true
if IP is private, '127.0.0.1' is used instead
----DEBUGGING-PEER-IP-END----
----DEBUGGING-PEER-IP-START----
remoteAddress: ::ffff:10.0.0.55
x-forwarded-for: 10.0.0.253
cf-connecting-ip: undefined
PairDrop uses: 10.0.0.253
IP is private: true
if IP is private, '127.0.0.1' is used instead
----DEBUGGING-PEER-IP-END----

What am I doing wrong here or what else can I check? This service works great for file transfers over the wifi but it would be cool to get it working over the internet (or at least using VPN).

Any hints would be greatly appreciated.

[ModernOctave]

I have a similar setup and am facing the same issue. Devices connected through the VPN are able to see each other and devices on the local network are able to see each other. However, devices on the VPN cannot see devices on the local network and vice versa. Even I think maybe it has something to do with them being on different subnet? Any help regarding this would be appreciated!

[schlagmichdoch]

For internet transfers (connections across different networks) you'll need to deploy a TURN server alongside PairDrop:
https://github.com/schlagmichdoch/PairDrop/blob/master/docs/host-your-own.md#turn-server-for-internet-transfer

enable fallback to websockets

Currently, the fallback only kicks in if devices cannot use WebRTC at all (e.g. switched off or not available).
As this was already confusing to users in the past, from v2.0 the fallback (if activated) will also kick in if the WebRTC connection fails with warning "TURN server needed" or alike. See #228