Files
nix/hosts/common/configs/system/kubernetes/options/default.nix
2025-01-29 16:16:17 +00:00

758 lines
25 KiB
Nix

{
config,
lib,
pkgs,
...
}:
let
cfg = config.services.kubernetes;
in
{
options.services.kubernetes =
with lib;
with types;
let
mkCertOptions = name: {
key = mkOption {
description = "${name} key file.";
type = path;
};
crt = mkOption {
description = "${name} certificate file.";
type = path;
};
};
in
{
enable = mkEnableOption "kubernetes";
lib = mkOption {
description = "Kubernetes utility functions.";
type = raw;
readOnly = true;
default = {
mkKubeConfig =
name: ca: cert: key:
(pkgs.formats.json { }).generate "${name}-kubeconfig.json" {
apiVersion = "v1";
kind = "Config";
clusters = [
{
name = "local";
cluster = {
server = cfg.apiserver._address;
"certificate-authority" = ca;
};
}
];
users = [
{
inherit name;
user = {
"client-certificate" = cert;
"client-key" = key;
};
}
];
contexts = [
{
name = "local";
context = {
cluster = "local";
user = name;
};
}
];
current-context = "local";
};
};
};
roles = mkOption {
description = "Kubernetes role that this machine should take.";
type = listOf (enum [
"master"
"node"
]);
default = [
"master"
"node"
];
};
address = mkOption {
description = "Kubernetes master server address.";
type = str;
default = "localhost";
};
cidr = mkOption {
description = "Kubernetes cluster CIDR.";
type = str;
default = "10.0.0.0/24";
};
cas = {
kubernetes = mkCertOptions "Kubernetes CA";
frontProxy = mkCertOptions "Front Proxy CA";
etcd = mkCertOptions "ETCD CA";
};
certs = {
apiserver = {
server = mkCertOptions "Kubernetes API Server";
kubeletClient = mkCertOptions "Kubernetes API Server Kubelet Client";
etcdClient = mkCertOptions "Kubernetes API Server ETCD Client";
};
etcd = {
server = mkCertOptions "ETCD Server";
peer = mkCertOptions "ETCD Peer";
};
frontProxy = mkCertOptions "Front Proxy Client";
serviceAccount = {
public = mkOption {
description = "Service account public key file.";
type = path;
};
private = mkOption {
description = "Service account private key file.";
type = path;
};
};
accounts = {
scheduler = mkCertOptions "Kubernetes Scheduler";
controllerManager = mkCertOptions "Kubernetes Controller Manager";
addonManager = mkCertOptions "Kubernetes Addon Manager";
proxy = mkCertOptions "Kubernetes Proxy";
admin = mkCertOptions "Kubernetes Admin";
};
};
kubeconfigs = mkOption {
description = "Kubernetes kubeconfigs.";
type = attrsOf path;
default = { };
};
apiserver = {
_address = mkOption {
description = "Kubernetes API server address.";
internal = true;
type = str;
};
address = mkOption {
description = "Kubernetes API server listening address.";
type = str;
readOnly = true;
default = "0.0.0.0";
};
port = mkOption {
description = "Kubernetes API server listening port.";
type = port;
readOnly = true;
default = 6443;
};
bootstrapTokenFile = mkOption {
description = "Kubernetes API server bootstrap token file.";
type = path;
};
};
kubelet = {
address = mkOption {
description = "Kubernetes kubelet listening address.";
type = str;
readOnly = true;
default = "0.0.0.0";
};
port = mkOption {
description = "Kubernetes kubelet listening port.";
type = port;
readOnly = true;
default = 10250;
};
taints =
let
taintOptions =
{ name, ... }:
{
key = mkOption {
description = "Taint key.";
type = str;
default = name;
};
value = mkOption {
description = "Taint value.";
type = str;
};
effect = mkOption {
description = "Taint effect.";
type = enum [
"NoSchedule"
"PreferNoSchedule"
"NoExecute"
];
};
};
in
mkOption {
description = "Taints to apply to the node.";
type = attrsOf (submodule taintOptions);
default = { };
};
bootstrapToken = mkOption {
description = "Kubelet bootstrap token file.";
type = path;
};
seedImages = mkOption {
description = "Container images to preload on the system.";
type = listOf package;
default = [ ];
};
cidr = mkOption {
description = "Kubernetes pod CIDR.";
type = str;
default = "10.1.0.0/16";
};
};
scheduler = {
address = mkOption {
description = "Kubernetes scheduler listening address.";
type = str;
readOnly = true;
default = "127.0.0.1";
};
port = mkOption {
description = "Kubernetes scheduler listening port.";
type = port;
readOnly = true;
default = 10251;
};
};
controllerManager = {
address = mkOption {
description = "Kubernetes controller manager listening address.";
type = str;
readOnly = true;
default = "127.0.0.1";
};
port = mkOption {
description = "Kubernetes controller manager listening port.";
type = port;
readOnly = true;
default = 10252;
};
};
proxy = {
address = mkOption {
description = "Kubernetes proxy listening address.";
type = str;
readOnly = true;
default = "0.0.0.0";
};
};
addonManager = {
addons = mkOption {
description = "Kubernetes addons.";
type = attrsOf (coercedTo (attrs) (a: [ a ]) (listOf attrs));
default = { };
};
bootstrapAddons = mkOption {
description = "Kubernetes addons applied with cluster-admin permissions.";
type = attrsOf (coercedTo (attrs) (a: [ a ]) (listOf attrs));
default = { };
};
};
};
config = lib.mkIf cfg.enable (
lib.mkMerge [
# master or node
{
services.kubernetes = {
apiserver._address = "https://${cfg.address}:${toString cfg.apiserver.port}";
kubeconfigs.admin =
cfg.lib.mkKubeConfig "admin" cfg.cas.kubernetes.crt cfg.certs.accounts.admin.crt
cfg.certs.accounts.admin.key;
addonManager.bootstrapAddons = {
addonManager = import ./addons/addon-manager { };
bootstrap = import ./addons/bootstrap { inherit config; };
kubeletApiAdmin = import ./addons/kubelet-api-admin { };
metricsServer = import ./addons/metrics-server { };
};
};
boot = {
kernel.sysctl = {
"net.bridge.bridge-nf-call-iptables" = 1;
"net.ipv4.ip_forward" = 1;
"net.bridge.bridge-nf-call-ip6tables" = 1;
};
kernelModules = [
"br_netfilter"
"overlay"
];
};
users = {
users.kubernetes = {
uid = config.ids.uids.kubernetes;
group = "kubernetes";
home = "/var/lib/kubernetes";
homeMode = "755";
createHome = true;
description = "Kubernetes user";
};
groups.kubernetes.gid = config.ids.gids.kubernetes;
};
systemd = {
targets.kubernetes = {
description = "Kubernetes";
wantedBy = [ "multi-user.target" ];
};
tmpfiles.rules = [
"d /opt/cni/bin 0755 root root -"
"d /run/kubernetes 0755 kubernetes kubernetes -"
];
services = {
kubelet =
let
kubeletConfig = (pkgs.formats.json { }).generate "config.json" ({
apiVersion = "kubelet.config.k8s.io/v1beta1";
kind = "KubeletConfiguration";
address = cfg.kubelet.address;
port = cfg.kubelet.port;
authentication = {
x509.clientCAFile = cfg.cas.kubernetes.crt;
webhook = {
enabled = true;
cacheTTL = "10s";
};
};
authorization.mode = "Webhook";
cgroupDriver = "systemd";
hairpinMode = "hairpin-veth";
registerNode = true;
containerRuntimeEndpoint = "unix:///run/containerd/containerd.sock";
failSwapOn = false;
memorySwap.swapBehavior = "LimitedSwap";
rotateCertificates = true;
serverTLSBootstrap = true;
featureGates = {
RotateKubeletServerCertificate = true;
NodeSwap = true;
};
healthzBindAddress = "127.0.0.1";
healthzPort = 10248;
});
taints = lib.strings.concatMapStringsSep "," (v: "${v.key}=${v.value}:${v.effect}") (
lib.attrsets.mapAttrsToList (n: v: v) cfg.kubelet.taints
);
generateKubeletBootstrapKubeconfig = lib.meta.getExe (
pkgs.writeShellApplication {
name = "kubelet-bootstrap-kubeconfig";
runtimeInputs = with pkgs; [ coreutils ];
text = ''
mkdir -p /etc/kubernetes
cat > /etc/kubernetes/bootstrap-kubeconfig <<EOF
apiVersion: v1
kind: Config
clusters:
- cluster:
certificate-authority: ${cfg.cas.kubernetes.crt}
server: ${cfg.apiserver._address}
name: local
contexts:
- context:
cluster: local
user: kubelet-bootstrap
name: bootstrap
current-context: bootstrap
preferences: {}
users:
- name: kubelet-bootstrap
user:
token: $(<${cfg.kubelet.bootstrapToken})
EOF
'';
}
);
seedContainerImages = lib.meta.getExe (
pkgs.writeShellApplication {
name = "seed-container-images";
runtimeInputs = with pkgs; [
gzip
containerd
coreutils
];
text = ''
${lib.strings.concatMapStrings (img: ''
echo "Seeding container image: ${img}"
${
if (lib.hasSuffix "gz" img) then
''zcat "${img}" | ctr -n k8s.io image import -''
else
''cat "${img}" | ctr -n k8s.io image import -''
}
'') cfg.kubelet.seedImages}
'';
}
);
in
{
description = "Kubernetes Kubelet";
wantedBy = [ "kubernetes.target" ];
after = [
"network.target"
"containerd.service"
"kube-apisever.service"
];
path = with pkgs; [
kubernetes
coreutils
util-linux
git
openssh
iproute2
ethtool
iptables
socat
thin-provisioning-tools
];
preStart = ''
${generateKubeletBootstrapKubeconfig}
${seedContainerImages}
'';
script = lib.strings.concatStringsSep " " (
[
"kubelet"
"--config=${kubeletConfig}"
"--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubeconfig"
"--kubeconfig=/var/lib/kubelet/kubeconfig"
"--cert-dir=/var/lib/kubelet/pki"
"--hostname-override=${lib.strings.toLower config.networking.fqdnOrHostName}"
"--kubeconfig=/etc/kubernetes/bootstrap-kubeconfig"
"--pod-infra-container-image=pause"
"--root-dir=/var/lib/kubelet"
]
++ lib.lists.optional (taints != "") [
"--register-with-taints=${taints}"
]
);
serviceConfig = {
Slice = "kubernetes.slice";
CPUAccounting = true;
MemoryAccounting = true;
Restart = "on-failure";
RestartSec = "1000ms";
WorkingDirectory = "/var/lib/kubelet";
};
unitConfig.StartLimitIntervalSec = 0;
};
kube-proxy = {
description = "Kubernetes Proxy";
wantedBy = [ "kubernetes.target" ];
after = [ "kube-apiserver.service" ];
path = with pkgs; [
kubernetes
iptables
conntrack-tools
];
script = lib.strings.concatStringsSep " " [
"kube-proxy"
"--bind-address=${cfg.proxy.address}"
"--cluster-cidr=${cfg.kubelet.cidr}"
"--hostname-override=${lib.strings.toLower config.networking.fqdnOrHostName}"
"--kubeconfig=${
cfg.lib.mkKubeConfig "kube-proxy" cfg.cas.kubernetes.crt cfg.certs.accounts.proxy.crt
cfg.certs.accounts.proxy.key
}"
];
serviceConfig = {
Slice = "kubernetes.slice";
WorkingDirectory = "/var/lib/kubernetes";
Restart = "on-failure";
RestartSec = 5;
};
unitConfig.StartLimitIntervalSec = 0;
};
};
};
networking.firewall.enable = false;
}
# only master
(lib.mkIf (lib.all (m: m == "master") cfg.roles) {
services.kubernetes.kubelet.taints = {
unschedulable = {
value = "true";
effect = "NoSchedule";
};
"node-role.kubernetes.io/master" = {
value = "true";
effect = "NoSchedule";
};
};
})
# master
(lib.mkIf (lib.elem "master" cfg.roles) {
services = {
etcd = {
enable = true;
name = cfg.address;
keyFile = cfg.certs.etcd.server.key;
certFile = cfg.certs.etcd.server.crt;
trustedCaFile = cfg.cas.etcd.crt;
peerKeyFile = cfg.certs.etcd.peer.key;
peerCertFile = cfg.certs.etcd.peer.crt;
peerTrustedCaFile = cfg.cas.etcd.crt;
clientCertAuth = true;
peerClientCertAuth = true;
listenClientUrls = [ "https://0.0.0.0:2379" ];
listenPeerUrls = [ "https://0.0.0.0:2380" ];
advertiseClientUrls = [ "https://${cfg.address}:2379" ];
initialCluster = [ "${cfg.address}=https://${cfg.address}:2380" ];
initialAdvertisePeerUrls = [ "https://${cfg.address}:2380" ];
};
};
systemd.services = {
kube-apiserver = {
description = "Kubernetes API Server";
wantedBy = [ "kubernetes.target" ];
after = [ "network.target" ];
path = with pkgs; [ kubernetes ];
script = lib.strings.concatStringsSep " " [
"kube-apiserver"
"--allow-privileged=true"
"--authorization-mode=RBAC,Node"
"--bind-address=${cfg.apiserver.address}"
"--secure-port=${toString cfg.apiserver.port}"
"--client-ca-file=${cfg.cas.kubernetes.crt}"
"--tls-cert-file=${cfg.certs.apiserver.server.crt}"
"--tls-private-key-file=${cfg.certs.apiserver.server.key}"
"--enable-admission-plugins=${
lib.strings.concatStringsSep "," [
"NamespaceLifecycle"
"LimitRanger"
"ServiceAccount"
"ResourceQuota"
"DefaultStorageClass"
"DefaultTolerationSeconds"
"NodeRestriction"
]
}"
"--etcd-servers=${
lib.strings.concatStringsSep "," [
"https://${cfg.address}:2379"
"https://127.0.0.1:2379"
]
}"
"--etcd-cafile=${cfg.cas.etcd.crt}"
"--etcd-certfile=${cfg.certs.apiserver.etcdClient.crt}"
"--etcd-keyfile=${cfg.certs.apiserver.etcdClient.key}"
"--kubelet-certificate-authority=${cfg.cas.kubernetes.crt}"
"--kubelet-client-certificate=${cfg.certs.apiserver.kubeletClient.crt}"
"--kubelet-client-key=${cfg.certs.apiserver.kubeletClient.key}"
"--proxy-client-cert-file=${cfg.certs.frontProxy.crt}"
"--proxy-client-key-file=${cfg.certs.frontProxy.key}"
"--runtime-config=authentication.k8s.io/v1beta1=true"
"--api-audiences=api,https://kubernetes.default.svc"
"--service-account-issuer=https://kubernetes.default.svc"
"--service-account-signing-key-file=${cfg.certs.serviceAccount.private}"
"--service-account-key-file=${cfg.certs.serviceAccount.public}"
"--service-cluster-ip-range=${cfg.cidr}"
"--storage-backend=etcd3"
"--enable-bootstrap-token-auth=true"
"--token-auth-file=${cfg.apiserver.bootstrapTokenFile}"
"--requestheader-client-ca-file=${cfg.cas.frontProxy.crt}"
"--requestheader-allowed-names=front-proxy-client"
"--requestheader-extra-headers-prefix=X-Remote-Extra-"
"--requestheader-group-headers=X-Remote-Group"
"--requestheader-username-headers=X-Remote-User"
];
serviceConfig = {
Slice = "kubernetes.slice";
WorkingDirectory = "/var/lib/kubernetes";
User = "kubernetes";
Group = "kubernetes";
AmbientCapabilities = "cap_net_bind_service";
Restart = "on-failure";
RestartSec = 5;
};
unitConfig.StartLimitIntervalSec = 0;
};
kube-scheduler = {
description = "Kubernetes Scheduler";
wantedBy = [ "kubernetes.target" ];
after = [ "kube-apiserver.service" ];
path = with pkgs; [ kubernetes ];
script = lib.strings.concatStringsSep " " [
"kube-scheduler"
"--bind-address=${cfg.scheduler.address}"
"--secure-port=${toString cfg.scheduler.port}"
"--leader-elect=true"
"--kubeconfig=${
cfg.lib.mkKubeConfig "kube-scheduler" cfg.cas.kubernetes.crt cfg.certs.accounts.scheduler.crt
cfg.certs.accounts.scheduler.key
}"
];
serviceConfig = {
Slice = "kubernetes.slice";
WorkingDirectory = "/var/lib/kubernetes";
User = "kubernetes";
Group = "kubernetes";
Restart = "on-failure";
RestartSec = 5;
};
unitConfig.StartLimitIntervalSec = 0;
};
kube-controller-manager = {
description = "Kubernetes Controller Manager";
wantedBy = [ "kubernetes.target" ];
after = [ "kube-apiserver.service" ];
path = with pkgs; [ kubernetes ];
script = lib.strings.concatStringsSep " " [
"kube-controller-manager"
"--allocate-node-cidrs=true"
"--bind-address=${cfg.controllerManager.address}"
"--secure-port=${toString cfg.controllerManager.port}"
"--cluster-cidr=${cfg.kubelet.cidr}"
"--kubeconfig=${
cfg.lib.mkKubeConfig "kube-controller-manager" cfg.cas.kubernetes.crt
cfg.certs.accounts.controllerManager.crt
cfg.certs.accounts.controllerManager.key
}"
"--leader-elect=true"
"--root-ca-file=${cfg.cas.kubernetes.crt}"
"--service-account-private-key-file=${cfg.certs.serviceAccount.private}"
"--use-service-account-credentials"
"--client-ca-file=${cfg.cas.kubernetes.crt}"
"--cluster-signing-cert-file=${cfg.cas.kubernetes.crt}"
"--cluster-signing-key-file=${cfg.cas.kubernetes.key}"
"--requestheader-client-ca-file=${cfg.cas.frontProxy.crt}"
];
serviceConfig = {
Slice = "kubernetes.slice";
Restart = "on-failure";
RestartSec = 30;
WorkingDirectory = "/var/lib/kubernetes";
User = "kubernetes";
Group = "kubernetes";
};
unitConfig.StartLimitIntervalSec = 0;
};
kube-addon-manager =
let
mkAddons =
addons:
lib.attrsets.mapAttrsToList (
name: addon:
(pkgs.formats.json { }).generate "${name}.json" {
apiVersion = "v1";
kind = "List";
items = addon;
}
) addons;
in
{
description = "Kubernetes Addon Manager";
wantedBy = [ "kubernetes.target" ];
after = [ "kube-apiserver.service" ];
environment = {
ADDON_PATH = pkgs.runCommand "kube-addons" { } ''
mkdir -p $out
${lib.strings.concatMapStringsSep "\n" (a: "ln -s ${a} $out/${baseNameOf a}") (
mkAddons cfg.addonManager.addons
)}
'';
KUBECONFIG =
cfg.lib.mkKubeConfig "addon-manager" cfg.cas.kubernetes.crt cfg.certs.accounts.addonManager.crt
cfg.certs.accounts.addonManager.key;
};
path = with pkgs; [
kubernetes
gawk
];
preStart = ''
export KUBECONFIG=${cfg.kubeconfigs.admin}
kubectl apply -f ${lib.strings.concatStringsSep " \\\n -f " (mkAddons cfg.addonManager.bootstrapAddons)}
'';
script = "kube-addons";
serviceConfig = {
Slice = "kubernetes.slice";
PermissionsStartOnly = true;
WorkingDirectory = "/var/lib/kubernetes";
User = "kubernetes";
Group = "kubernetes";
Restart = "on-failure";
RestartSec = 10;
};
unitConfig.StartLimitIntervalSec = 0;
};
};
})
# node
(lib.mkIf (lib.elem "node" cfg.roles) {
virtualisation.containerd = {
enable = true;
settings = {
version = 2;
root = "/var/lib/containerd";
state = "/run/containerd";
oom_score = 0;
grpc.address = "/run/containerd/containerd.sock";
plugins."io.containerd.grpc.v1.cri" = {
containerd.runtimes.runc = {
runtime_type = "io.containerd.runc.v2";
options.SystemdCgroup = true;
};
};
};
};
})
]
);
}