Raspberry Pi 4 looks interesting.

[agent_kith]

There is something quirky about the networking stack on the Raspberry Pi 4. But I can't figure out what exactly it is.

I'm using a new firewall software at the moment (Untangle), and the Pi just straight up refuse to work. And then there's the problem of using Pi in a jumbo frame network environment isn't helping (Pi4 still don't work with Jumbo Frames AFAIK).

You can disable Jumbo frames by adding the following lines to "/etc/sysctl.conf" (Requires restart).

Code:

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

Also check if your NAS is using Jumbo frames. If it is, disable it.