Use k0s's RunDir for keepalived config file

The file is ephemeral and doesn't need to live on a persistent path.
This also saves us from ensuring the existence of the base directory
in the cplb component, as the RunDir's existence is ensured during
controller startup.

Signed-off-by: Tom Wieczorek <twieczorek@mirantis.com>

pkg/component/controller/cplb_unix.go

@@ -29,7 +29,6 @@ import (
 	"slices"
 	"text/template"
 
-	"github.com/k0sproject/k0s/internal/pkg/dir"
 	"github.com/k0sproject/k0s/internal/pkg/users"
 	k0sAPI "github.com/k0sproject/k0s/pkg/apis/k0s/v1beta1"
 	"github.com/k0sproject/k0s/pkg/assets"
@@ -42,11 +41,12 @@ import (
 
 // Keepalived is the controller for the keepalived process in the control plane load balancing
 type Keepalived struct {
-	K0sVars    *config.CfgVars
-	Config     *k0sAPI.ControlPlaneLoadBalancingSpec
-	uid        int
-	supervisor *supervisor.Supervisor
-	log        *logrus.Entry
+	K0sVars        *config.CfgVars
+	Config         *k0sAPI.ControlPlaneLoadBalancingSpec
+	uid            int
+	supervisor     *supervisor.Supervisor
+	log            *logrus.Entry
+	configFilePath string
 }
 
 // Init extracts the needed binaries and creates the directories
@@ -62,15 +62,7 @@ func (k *Keepalived) Init(_ context.Context) error {
 		k.log.Warnf("Unable to get %s UID running keepalived as root: %v", constant.KeepalivedUser, err)
 	}
 
-	basepath := filepath.Dir(k.K0sVars.KeepalivedConfigFile)
-	if err = dir.Init(basepath, constant.KeepalivedDirMode); err != nil {
-		return fmt.Errorf("failed to create keepalived data dir: %v", err)
-	}
-
-	if err = os.Chown(basepath, k.uid, -1); err != nil {
-		return fmt.Errorf("failed to chown keepalived data dir: %v", err)
-	}
-
+	k.configFilePath = filepath.Join(k.K0sVars.RunDir, "keepalived.conf")
 	return assets.Stage(k.K0sVars.BinDir, "keepalived", constant.BinDirMode)
 }
 
@@ -99,7 +91,7 @@ func (k *Keepalived) Start(_ context.Context) error {
 		Args: []string{
 			"--dont-fork",
 			"--use-file",
-			k.K0sVars.KeepalivedConfigFile,
+			k.configFilePath,
 		},
 		RunDir:  k.K0sVars.RunDir,
 		DataDir: k.K0sVars.DataDir,
@@ -265,7 +257,7 @@ func (*Keepalived) getLinkAddresses(link netlink.Link) ([]netlink.Addr, []string
 }
 
 func (k *Keepalived) generateKeepalivedTemplate() error {
-	f, err := os.OpenFile(k.K0sVars.KeepalivedConfigFile, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, fs.FileMode(0500))
+	f, err := os.OpenFile(k.configFilePath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, fs.FileMode(0500))
 	if err != nil {
 		return fmt.Errorf("failed to open keepalived config file: %v", err)
 	}
@@ -284,10 +276,10 @@ func (k *Keepalived) generateKeepalivedTemplate() error {
 	}
 
 	// TODO: Do we really need to this every single time?
-	if err = os.Chown(k.K0sVars.KeepalivedConfigFile, k.uid, -1); err != nil {
+	if err = os.Chown(k.configFilePath, k.uid, -1); err != nil {
 		return fmt.Errorf("failed to chown keepalived config file: %v", err)
 	}
-	if err = os.Chmod(k.K0sVars.KeepalivedConfigFile, fs.FileMode(0400)); err != nil {
+	if err = os.Chmod(k.configFilePath, fs.FileMode(0400)); err != nil {
 		return fmt.Errorf("failed to chmod keepalived config file: %v", err)
 	}
 	return nil

pkg/config/cfgvars.go

@@ -49,7 +49,6 @@ type CfgVars struct {
 	EtcdCertDir                string // EtcdCertDir contains etcd certificates
 	EtcdDataDir                string // EtcdDataDir contains etcd state
 	KineSocketPath             string // The unix socket path for kine
-	KeepalivedConfigFile       string // location for keepalived data
 	KonnectivitySocketDir      string // location of konnectivity's socket path
 	KubeletAuthConfigPath      string // KubeletAuthConfigPath defines the default kubelet auth config path
 	KubeletVolumePluginDir     string // location for kubelet plugins volume executables
@@ -179,7 +178,6 @@ func NewCfgVars(cobraCmd command, dirs ...string) (*CfgVars, error) {
 		EtcdCertDir:                filepath.Join(certDir, "etcd"),
 		EtcdDataDir:                filepath.Join(dataDir, "etcd"),
 		KineSocketPath:             filepath.Join(runDir, constant.KineSocket),
-		KeepalivedConfigFile:       filepath.Join(dataDir, "keepalived", "keepalived.conf"),
 		KonnectivitySocketDir:      filepath.Join(runDir, "konnectivity-server"),
 		KubeletAuthConfigPath:      filepath.Join(dataDir, "kubelet.conf"),
 		KubeletVolumePluginDir:     constant.KubeletVolumePluginDir,