RPC server failed to bind TCP localhost:5279

Bug When I try starting the app I get I have installed the app from flatpak, previously it worked. I didn’t update or anything however. Nothing seems to be running on given port.

To Reproduce On my system, I just try to start app, I do not know how to reproduce it on any system.

Expected behavior App starts

System Configuration

curl 'http://localhost:5279' --data '{"method":"version"}' results in curl: (7) Failed to connect to localhost port 5279: Connection refused

• LBRY Daemon version:
• LBRY App version: 0.49.4
• LBRY Installation ID:
• Operating system: Pop OS 20.10 (Ubuntu)

Additional context When I try to run it from command line I get following

[3 preload-host-spawn-strategy] Running: /app/bin/zypak-helper child - /app/lbry-app/lbry-app --type=zygote
Gtk-Message: 22:12:09.167: Failed to load module "appmenu-gtk-module"
Gtk-Message: 22:12:09.244: Failed to load module "canberra-gtk-module"
Gtk-Message: 22:12:09.244: Failed to load module "canberra-gtk-module"
Starting SDK
Sandbox listening on port 5278.
Daemon: 2021-02-02 22:12:10,577 INFO     lbry.extras.daemon.daemon:486: Starting LBRYNet Daemon

Daemon: 2021-02-02 22:12:10,579 INFO     lbry.extras.daemon.daemon:488: Platform: {
  "processor": "",
  "python_version": "3.7.9",
  "platform": "Linux-5.8.0-7630-generic-x86_64-with-glibc2.4",
  "os_release": "5.8.0-7630-generic",
  "os_system": "Linux",
  "lbrynet_version": "0.88.0",
  "version": "0.88.0",
  "build": "release",
  "distro": {
    "id": "org.freedesktop.platform",
    "version": "20.08.3",
    "version_parts": {
      "major": "20",
      "minor": "08",
      "build_number": "3"
    },
    "like": "",
    "codename": "Flatpak runtime"
  },
  "desktop": "Unity"
}

Daemon: 2021-02-02 22:12:10,581 ERROR    lbry.extras.daemon.daemon:504: RPC server failed to bind TCP localhost:5279

Daemon: 2021-02-02 22:12:10,582 INFO     lbry.extras.daemon.daemon:569: stopped api components

Daemon: 2021-02-02 22:12:10,582 INFO     lbry.extras.daemon.daemon:573: stopped api server

Daemon: 2021-02-02 22:12:10,582 INFO     lbry.extras.daemon.daemon:576: finished shutting down

[Pealouse]

The application attempts to bind to “localhost”, but you probably have both an IPv4 (127.0.0.1) and an IPv6 (::1) version of “localhost” defined in your /etc/hosts file and the application is ending up with the IPv6 version.

Since you have IPv6 disabled, trying to bind to ::1 fails. If you comment out the IPv6 version of localhost (or enable IPv6), it should work.

[Tony4dev]

This is not an issue with the app, but rather something on your local network / ipv6 config that prevents binding on localhost.

Try the config at the bottom of the previously mentioned FAQ which accesses 127.0.0.1 instead. Please post a new log file when you add that (the sdk/app must be restarted in between).

What role does ipv6 plays in this? I have ipv6 turned off, and it has to stay like that, with following commands

sudo sysctl -w net.ipv6.conf.all.disable_ipv6=1
sudo sysctl -w net.ipv6.conf.default.disable_ipv6=1
sudo sysctl -w net.ipv6.conf.lo.disable_ipv6=1

The reason why i said FAQ doesn’t help is because it doesn’t when I create the daemon_settings.yml it seems to not do anything. The output is the SAME as before. Is that because it is a flatpak app? How do I start the flatpak app with the parameters -api etc…