83 lines
3.2 KiB
Nix
83 lines
3.2 KiB
Nix
{config, ...}: {
|
|
# https://wiki.nixos.org/wiki/Networking
|
|
# https://wiki.nixos.org/wiki/Systemd-networkd
|
|
|
|
networking = {
|
|
firewall = {
|
|
# Allow some ports for ad-hoc use
|
|
allowedTCPPorts = [1234 1337 8000 8080];
|
|
allowedUDPPorts = [1234 1337 8000 8080];
|
|
# Do not spam dmesg/journalctl with refused connections
|
|
logRefusedConnections = false;
|
|
};
|
|
nameservers = [
|
|
"159.69.4.2#dns.caspervk.net"
|
|
"2a01:4f8:1c0c:70d1::1#dns.caspervk.net"
|
|
];
|
|
search = ["caspervk.net"];
|
|
};
|
|
|
|
# TODO: these systemd networkd settings will be the default once
|
|
# https://github.com/NixOS/nixpkgs/pull/264967 is merged.
|
|
networking.useNetworkd = true;
|
|
systemd.network.enable = true;
|
|
|
|
# The notion of "online" is a broken concept
|
|
# https://github.com/nix-community/srvos/blob/main/nixos/common/networking.nix
|
|
systemd.services.NetworkManager-wait-online.enable = false;
|
|
systemd.network.wait-online.enable = false;
|
|
|
|
# systemd-resolved provides DNS resolution to local applications through
|
|
# D-Bus, NSS, and a local stub resolver on 127.0.0.53. It implements caching
|
|
# and DNSSEC validation. We configure it to only, and always, use
|
|
# dns.caspervk.net over TLS.
|
|
# NOTE: It's surprisingly hard to get the system to always follow the custom
|
|
# DNS servers rather than the DHCP-provided ones. Check the traffic with:
|
|
# > sudo tcpdump -n --interface=any '(udp port 53) or (tcp port 853)'
|
|
# or
|
|
# > sudo resolvectl log-level debug
|
|
# > sudo journalctl -fu systemd-resolved.service
|
|
# https://wiki.nixos.org/wiki/Encrypted_DNS
|
|
# https://wiki.nixos.org/wiki/Systemd-resolved
|
|
services.resolved = {
|
|
enable = true;
|
|
dnsovertls = "true";
|
|
# TODO: DNSSEC support in systemd-resolved is considered experimental and
|
|
# incomplete. Upstream will validate for us anyway, and we trust it.
|
|
# https://wiki.archlinux.org/title/systemd-resolved#DNSSEC
|
|
dnssec = "false";
|
|
# 'Domains' is used for two distinct purposes; first, any domains *not*
|
|
# prefixed with '~' are used as search suffixes when resolving single-label
|
|
# hostnames into FQDNs. The NixOS default is to set this to
|
|
# `config.networking.search`, which we maintain. Second, domains prefixed
|
|
# with '~' ("route-only domains") define a search path that preferably
|
|
# directs DNS queries to this interface. The '~.' construct use the DNS
|
|
# servers defined here preferably for the root (all) domain(s).
|
|
# https://man.archlinux.org/man/resolved.conf.5
|
|
domains = config.networking.search ++ ["~."];
|
|
# Resolved falls back to DNS servers operated by American internet
|
|
# surveillance and adtech companies by default. No thanks, I'd rather have
|
|
# no DNS at all.
|
|
fallbackDns = [];
|
|
};
|
|
|
|
# TCP BBR has significantly increased throughput and reduced latency. Note
|
|
# that the IPv4 setting controls both IPv4 and IPv6.
|
|
boot.kernel.sysctl = {
|
|
"net.ipv4.tcp_congestion_control" = "bbr";
|
|
};
|
|
|
|
# vnStat keeps a log of hourly, daily and monthly network traffic
|
|
services.vnstat.enable = true;
|
|
environment.persistence."/nix/persist" = {
|
|
directories = [
|
|
{
|
|
directory = "/var/lib/vnstat";
|
|
user = "root";
|
|
group = "root";
|
|
mode = "0755";
|
|
}
|
|
];
|
|
};
|
|
}
|