Virtual Box / Linux Mint / Host Windows 10 - Bitcoin Core can't connect to peers

[Arman The Parman]

Hello,
I've so far successfully installed VirtualBox, Linux Mint, and prepared an external drive, downloaded Bitcoin Core latest version 0.20.1.
I've loaded bitcoin-qt, and it is stuck tyring to connect to a peer. There is no network traffic reported by Bitcoin-qt.

My internet connection is fine.
The computer is a Surface Pro, running windows 10, and it is connected to the home network by Wifi.

I am not an expert at networking, and wondered if I need to tweak any settings. Would appreciate help.

Arman The Parman
(@parman_the)

[1715454732]

1715454732

[1715454732]

1715454732

[Arman The Parman]

My troubleshooting results so far:

When I disconnected from my home Wi-Fi and connected to my mobile phone's hotspot.
It works!

So the problem must be with my home network.

It is strange because I have several Nodes that are function on the same network, but they are all connected by Ethernet. Wi-Fi on two different computers does not allow Bitcoin Core to connect to peers. What could this mean?

[Arman The Parman]

Solved.

It was the Firewall setting on the router. It was set to high. Strange that it only affects my Wi-Fi nodes and not ethernet nodes.

[NotATether]

Solved.

It was the Firewall setting on the router. It was set to high. Strange that it only affects my Wi-Fi nodes and not ethernet nodes.

Lots of firewalls built-in to routers are known to block traffic on non-standard ports, like port 8333 that's used by bitcoin-qt. They only allow a handful of ports which ISPs expect their consumers to use like ports 80 (HTTP), 443 (HTTPS) port 53 DNS, and some others, and they block the rest of the ports.

Some routers do the reverse and only block traffic from ports the ISP doesn't like, like Bittorrent and proxy server ports.