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|
#import "@preview/polylux:0.4.0": *
#import "@preview/metropolis-polylux:0.1.0" as metropolis
#show: metropolis.setup
#show: metropolis.setup.with(footer: [NixOS on routers])
#slide[
#set page(header: none, footer: none, margin: 3em)
#text(size: 1.3em)[*NixOS on routers*]
Fosdem 2026
#metropolis.divider
#set text(size: .8em, weight: "light")
Karel Kočí
31.01.2026
]
#metropolis.new-section[Why?]
#slide[
= Why?
#toolbox.side-by-side[
- Unified deployment
- Unified management
- Unified monitoring
- Unified tools
][
#set align(center)
#image("unified.png")
]
- Reproducible
]
#slide[
#set page(header: none, footer: none, margin: 0em)
#set align(center)
#grid(
columns: (50%, 50%),
rows: (47%, 53%),
image("omnia.jpg"),
image("mox.jpg"),
image("ssh-omnia.png"),
image("ssh-mox.png"),
)
]
#metropolis.new-section[Network Setup]
#slide[
= SystemD Networkd
#set text(18pt)
```nix
boot.kernel.sysctl."net.ipv6.conf.all.forwarding" = 1;
networking.useNetworkd = true;
systemd.network = {
"eth1" = {
matchConfig.Name = "eth1";
networkConfig = {
Address = "192.168.1.1/24";
IPv4Forwarding = "yes"; DHCPServer = "yes"; DHCPPrefixDelegation = "yes";
IPv6Forwarding = "yes"; IPv6SendRA = "yes"; IPv6AcceptRA = "no";
};
dhcpServerConfig = {
UplinkInterface = "eth0";
PoolOffset = 100; PoolSize = 100;
};
dhcpPrefixDelegationConfig = {
UplinkInterface = "eth0"; SubnetId = 1; Announce = "yes";
};
};
};
```
]
#slide[
= Resolved
#set text(18pt)
```nix
services.resolved = {
enable = true;
settings.Resolve = {
DNSStubListenerExtra=["192.168.1.1"];
FallbackDNS = ["1.1.1.1" "8.8.8.8"];
};
};
systemd.network."eth1".dhcpServerConfig = {
EmitDNS = "yes";
DNS = "192.168.1.1";
};
```
]
#slide[
= Firewall
#set text(18pt)
```nix
networking.firewall = {
interfaces."eth1".allowedUDPPorts = [
53 67 68
];
nat = {
enable = true;
externalInterface = "eth0";
internalInterfaces = ["eth1"];
};
};
```
]
#metropolis.new-section[Choosing Hardware]
#slide[
= Hardware Requirements
- 2-\? Ethernet interfaces
- Wi-Fi?
- Storage (NixOS at least 16G): NVMe / mSD card
- CPU architecture: Watts vs. support
]
#slide[
= SOHO Router
#set align(top)
Commonly ARMv7l or AArch64.
#toolbox.side-by-side[
== Advantages
- Small form factor
- Lower power consumption
][
== Disadvantages
- Harder to get running
- Requires cross-compilation
- ARMv7l on NixOS is pain
]
]
#slide[
= x84_64 with PCIe cards
#set align(top)
#toolbox.side-by-side[
== Advantages
- Architecture fully supported
- Not different from server
- More powerful for service hosting
][
== Disadvantages
- Possibly higher power consumption
- Large form factor
]
#set align(horizon)
Most likely better paired with SOHO for Wi-Fi and non-NixOS switch.
]
#slide[
= Bonus: Porting to ARM
```nix
nixpkgs.hostPlatform.system = "armv7l-linux";
boot = {
loader = {
grub.enable = false;
systemd-boot.enable = false;
generic-extlinux-compatible.enable = true;
};
kernelPackages = pkgs.linuxPackagesFor pkgs.linux_6_1_turris_omnia;
initrd.includeDefaultModules = false;
kernelParams = [ "earlyprintk" "console=ttyS0,115200" ];
kernelModules = [ "leds_turris_omnia" ];
initrd.availableKernelModules = [ "ahci_mvebu" "rtc_armada38x" ];
};
```
]
#slide[
#show: metropolis.focus
Thank you
Karel Kočí
#metropolis.divider
#text(size: 0.7em)[
https://gitlab.com/Cynerd/nixos-personal
https://git.cynerd.cz/presentations/tree/2026-fosdem
]
]
|
