(Re)onnect breaks Qbittorrent-nox connectivity

[TobiasS1402]

Setup:

• Qbittorrent-nox 4.3.6
• TrueNAS Jail 12.2-RELEASE
• ipfw that allows only ingoing/outgoing traffic to my tun0 interface created by openvpn
• options -> advanced -> network interface is set to tun0

How to reproduce:

• Reconnect openvpn while qbittorrent is running or restart the jail where qbittorrent, IPFW and openvpn are set to start at boot.

Outcome:

• The connection status is red, the DHT nodes are 0 and there is no traffic going on.

Expected outcome:

• Nodes are not 0 and there is traffic going on.

Logging:

(I) 2021-08-01T22:28:24 - Network configuration of tun0 has changed, refreshing session binding
(I) 2021-08-01T22:28:24 - Trying to listen on: tun0:35278
(N) 2021-08-01T22:28:53 - WebAPI login success. IP: ::ffff:192.168.1.2

[TobiasS1402]

Restarting the Qbittorrent-nox service after the vpn connection has been established solves this issue.

[ghost]

arvidn/libtorrent#4412

[TobiasS1402]

#10790 (comment) found a working fix for my environment. So i set it from 'All addresses' to 'All IPV4 addresses' and now after a network change qbittorrent reconnects and the DHT nodes come back up and i receive and send data.

[ghost]

@arvidn
In this case user chose All IPv4 address which translates to 0.0.0.0:port instead of all addresses (0.0.0.0:port,[::]:port) which fixed the issue for him described in OP.

[Forza-tng]

@arvidn
In this case user chose All IPv4 address which translates to 0.0.0.0:port instead of all addresses (0.0.0.0:port,[::]:port) which fixed the issue for him described in OP.

This is dangerous because qBitttorrent would use any address, no matter if it is over VPN or not. When VPN is down, qBitttorrent use the normal network which is unprotected.

[finnzz]

Setting to all IPv4 worked for me, along with having my VPN interface right above.

Now when the VPN goes offline, torrents stop and start again when the VPN reconnects.

[arvidn]

if you want to use a specific interface, the listen_interfaces setting should be set to that interface name specifically. If it goes away, nothing will work. If it comes back, things will work again.

[finnzz]

if you want to use a specific interface, the listen_interfaces setting should be set to that interface name specifically. If it goes away, nothing will work. If it comes back, things will work again.

By 'listen interface' you do you mean 'Network interface' setting above 'optional IP address to bind to'?

Currently I have the Network interface set to my VPN connection, and 'all IPV4 addresses'. Is there anything else I should be modifying? This seems to be enough to get the torrents to stop and start with the VPN connection.