593 lines
16 KiB
Go
593 lines
16 KiB
Go
//+build linux,lxc
|
|
|
|
package driver
|
|
|
|
import (
|
|
"context"
|
|
"encoding/json"
|
|
"fmt"
|
|
"log"
|
|
"os"
|
|
"path/filepath"
|
|
"strconv"
|
|
"strings"
|
|
"syscall"
|
|
"time"
|
|
|
|
"github.com/hashicorp/nomad/client/fingerprint"
|
|
"github.com/hashicorp/nomad/client/stats"
|
|
"github.com/hashicorp/nomad/helper/fields"
|
|
"github.com/hashicorp/nomad/nomad/structs"
|
|
"github.com/mitchellh/mapstructure"
|
|
|
|
dstructs "github.com/hashicorp/nomad/client/driver/structs"
|
|
cstructs "github.com/hashicorp/nomad/client/structs"
|
|
lxc "gopkg.in/lxc/go-lxc.v2"
|
|
)
|
|
|
|
const (
|
|
// lxcConfigOption is the key for enabling the LXC driver in the
|
|
// Config.Options map.
|
|
lxcConfigOption = "driver.lxc.enable"
|
|
|
|
// lxcVolumesConfigOption is the key for enabling the use of
|
|
// custom bind volumes to arbitrary host paths
|
|
lxcVolumesConfigOption = "lxc.volumes.enabled"
|
|
lxcVolumesConfigDefault = true
|
|
|
|
// containerMonitorIntv is the interval at which the driver checks if the
|
|
// container is still alive
|
|
containerMonitorIntv = 2 * time.Second
|
|
)
|
|
|
|
var (
|
|
LXCMeasuredCpuStats = []string{"System Mode", "User Mode", "Percent"}
|
|
|
|
LXCMeasuredMemStats = []string{"RSS", "Cache", "Swap", "Max Usage", "Kernel Usage", "Kernel Max Usage"}
|
|
)
|
|
|
|
// Add the lxc driver to the list of builtin drivers
|
|
func init() {
|
|
BuiltinDrivers["lxc"] = NewLxcDriver
|
|
}
|
|
|
|
// LxcDriver allows users to run LXC Containers
|
|
type LxcDriver struct {
|
|
DriverContext
|
|
fingerprint.StaticFingerprinter
|
|
}
|
|
|
|
// LxcDriverConfig is the configuration of the LXC Container
|
|
type LxcDriverConfig struct {
|
|
Template string
|
|
Distro string
|
|
Release string
|
|
Arch string
|
|
ImageVariant string `mapstructure:"image_variant"`
|
|
ImageServer string `mapstructure:"image_server"`
|
|
GPGKeyID string `mapstructure:"gpg_key_id"`
|
|
GPGKeyServer string `mapstructure:"gpg_key_server"`
|
|
DisableGPGValidation bool `mapstructure:"disable_gpg"`
|
|
FlushCache bool `mapstructure:"flush_cache"`
|
|
ForceCache bool `mapstructure:"force_cache"`
|
|
TemplateArgs []string `mapstructure:"template_args"`
|
|
LogLevel string `mapstructure:"log_level"`
|
|
Verbosity string
|
|
Volumes []string `mapstructure:"volumes"`
|
|
}
|
|
|
|
// NewLxcDriver returns a new instance of the LXC driver
|
|
func NewLxcDriver(ctx *DriverContext) Driver {
|
|
return &LxcDriver{DriverContext: *ctx}
|
|
}
|
|
|
|
// Validate validates the lxc driver configuration
|
|
func (d *LxcDriver) Validate(config map[string]interface{}) error {
|
|
fd := &fields.FieldData{
|
|
Raw: config,
|
|
Schema: map[string]*fields.FieldSchema{
|
|
"template": {
|
|
Type: fields.TypeString,
|
|
Required: true,
|
|
},
|
|
"distro": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"release": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"arch": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"image_variant": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"image_server": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"gpg_key_id": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"gpg_key_server": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"disable_gpg": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"flush_cache": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"force_cache": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"template_args": {
|
|
Type: fields.TypeArray,
|
|
Required: false,
|
|
},
|
|
"log_level": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"verbosity": {
|
|
Type: fields.TypeString,
|
|
Required: false,
|
|
},
|
|
"volumes": {
|
|
Type: fields.TypeArray,
|
|
Required: false,
|
|
},
|
|
},
|
|
}
|
|
|
|
if err := fd.Validate(); err != nil {
|
|
return err
|
|
}
|
|
|
|
volumes, _ := fd.GetOk("volumes")
|
|
for _, volDesc := range volumes.([]interface{}) {
|
|
volStr := volDesc.(string)
|
|
paths := strings.Split(volStr, ":")
|
|
if len(paths) != 2 {
|
|
return fmt.Errorf("invalid volume bind mount entry: '%s'", volStr)
|
|
}
|
|
if len(paths[0]) == 0 || len(paths[1]) == 0 {
|
|
return fmt.Errorf("invalid volume bind mount entry: '%s'", volStr)
|
|
}
|
|
if paths[1][0] == '/' {
|
|
return fmt.Errorf("unsupported absolute container mount point: '%s'", paths[1])
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (d *LxcDriver) Abilities() DriverAbilities {
|
|
return DriverAbilities{
|
|
SendSignals: false,
|
|
Exec: false,
|
|
}
|
|
}
|
|
|
|
func (d *LxcDriver) FSIsolation() cstructs.FSIsolation {
|
|
return cstructs.FSIsolationImage
|
|
}
|
|
|
|
// Fingerprint fingerprints the lxc driver configuration
|
|
func (d *LxcDriver) Fingerprint(req *cstructs.FingerprintRequest, resp *cstructs.FingerprintResponse) error {
|
|
cfg := req.Config
|
|
|
|
enabled := cfg.ReadBoolDefault(lxcConfigOption, true)
|
|
if !enabled && !cfg.DevMode {
|
|
return nil
|
|
}
|
|
version := lxc.Version()
|
|
if version == "" {
|
|
return nil
|
|
}
|
|
resp.AddAttribute("driver.lxc.version", version)
|
|
resp.AddAttribute("driver.lxc", "1")
|
|
resp.Detected = true
|
|
|
|
// Advertise if this node supports lxc volumes
|
|
if d.config.ReadBoolDefault(lxcVolumesConfigOption, lxcVolumesConfigDefault) {
|
|
resp.AddAttribute("driver."+lxcVolumesConfigOption, "1")
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (d *LxcDriver) Prestart(*ExecContext, *structs.Task) (*PrestartResponse, error) {
|
|
return nil, nil
|
|
}
|
|
|
|
// Start starts the LXC Driver
|
|
func (d *LxcDriver) Start(ctx *ExecContext, task *structs.Task) (*StartResponse, error) {
|
|
sresp, err, errCleanup := d.startWithCleanup(ctx, task)
|
|
if err != nil {
|
|
if cleanupErr := errCleanup(); cleanupErr != nil {
|
|
d.logger.Printf("[ERR] error occurred while cleaning up from error in Start: %v", cleanupErr)
|
|
}
|
|
}
|
|
return sresp, err
|
|
}
|
|
|
|
func (d *LxcDriver) startWithCleanup(ctx *ExecContext, task *structs.Task) (*StartResponse, error, func() error) {
|
|
noCleanup := func() error { return nil }
|
|
var driverConfig LxcDriverConfig
|
|
if err := mapstructure.WeakDecode(task.Config, &driverConfig); err != nil {
|
|
return nil, err, noCleanup
|
|
}
|
|
lxcPath := lxc.DefaultConfigPath()
|
|
if path := d.config.Read("driver.lxc.path"); path != "" {
|
|
lxcPath = path
|
|
}
|
|
|
|
containerName := fmt.Sprintf("%s-%s", task.Name, d.DriverContext.allocID)
|
|
c, err := lxc.NewContainer(containerName, lxcPath)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("unable to initialize container: %v", err), noCleanup
|
|
}
|
|
|
|
var verbosity lxc.Verbosity
|
|
switch driverConfig.Verbosity {
|
|
case "verbose":
|
|
verbosity = lxc.Verbose
|
|
case "", "quiet":
|
|
verbosity = lxc.Quiet
|
|
default:
|
|
return nil, fmt.Errorf("lxc driver config 'verbosity' can only be either quiet or verbose"), noCleanup
|
|
}
|
|
c.SetVerbosity(verbosity)
|
|
|
|
var logLevel lxc.LogLevel
|
|
switch driverConfig.LogLevel {
|
|
case "trace":
|
|
logLevel = lxc.TRACE
|
|
case "debug":
|
|
logLevel = lxc.DEBUG
|
|
case "info":
|
|
logLevel = lxc.INFO
|
|
case "warn":
|
|
logLevel = lxc.WARN
|
|
case "", "error":
|
|
logLevel = lxc.ERROR
|
|
default:
|
|
return nil, fmt.Errorf("lxc driver config 'log_level' can only be trace, debug, info, warn or error"), noCleanup
|
|
}
|
|
c.SetLogLevel(logLevel)
|
|
|
|
logFile := filepath.Join(ctx.TaskDir.Dir, fmt.Sprintf("%v-lxc.log", task.Name))
|
|
c.SetLogFile(logFile)
|
|
|
|
options := lxc.TemplateOptions{
|
|
Template: driverConfig.Template,
|
|
Distro: driverConfig.Distro,
|
|
Release: driverConfig.Release,
|
|
Arch: driverConfig.Arch,
|
|
FlushCache: driverConfig.FlushCache,
|
|
DisableGPGValidation: driverConfig.DisableGPGValidation,
|
|
ExtraArgs: driverConfig.TemplateArgs,
|
|
}
|
|
|
|
if err := c.Create(options); err != nil {
|
|
return nil, fmt.Errorf("unable to create container: %v", err), noCleanup
|
|
}
|
|
|
|
// Set the network type to none
|
|
if err := c.SetConfigItem("lxc.network.type", "none"); err != nil {
|
|
return nil, fmt.Errorf("error setting network type configuration: %v", err), c.Destroy
|
|
}
|
|
|
|
// Bind mount the shared alloc dir and task local dir in the container
|
|
mounts := []string{
|
|
fmt.Sprintf("%s local none rw,bind,create=dir", ctx.TaskDir.LocalDir),
|
|
fmt.Sprintf("%s alloc none rw,bind,create=dir", ctx.TaskDir.SharedAllocDir),
|
|
fmt.Sprintf("%s secrets none rw,bind,create=dir", ctx.TaskDir.SecretsDir),
|
|
}
|
|
|
|
volumesEnabled := d.config.ReadBoolDefault(lxcVolumesConfigOption, lxcVolumesConfigDefault)
|
|
|
|
for _, volDesc := range driverConfig.Volumes {
|
|
// the format was checked in Validate()
|
|
paths := strings.Split(volDesc, ":")
|
|
|
|
if filepath.IsAbs(paths[0]) {
|
|
if !volumesEnabled {
|
|
return nil, fmt.Errorf("absolute bind-mount volume in config but '%v' is false", lxcVolumesConfigOption), c.Destroy
|
|
}
|
|
} else {
|
|
// Relative source paths are treated as relative to alloc dir
|
|
paths[0] = filepath.Join(ctx.TaskDir.Dir, paths[0])
|
|
}
|
|
|
|
mounts = append(mounts, fmt.Sprintf("%s %s none rw,bind,create=dir", paths[0], paths[1]))
|
|
}
|
|
|
|
for _, mnt := range mounts {
|
|
if err := c.SetConfigItem("lxc.mount.entry", mnt); err != nil {
|
|
return nil, fmt.Errorf("error setting bind mount %q error: %v", mnt, err), c.Destroy
|
|
}
|
|
}
|
|
|
|
// Start the container
|
|
if err := c.Start(); err != nil {
|
|
return nil, fmt.Errorf("unable to start container: %v", err), c.Destroy
|
|
}
|
|
|
|
stopAndDestroyCleanup := func() error {
|
|
if err := c.Stop(); err != nil {
|
|
return err
|
|
}
|
|
return c.Destroy()
|
|
}
|
|
|
|
// Set the resource limits
|
|
if err := c.SetMemoryLimit(lxc.ByteSize(task.Resources.MemoryMB) * lxc.MB); err != nil {
|
|
return nil, fmt.Errorf("unable to set memory limits: %v", err), stopAndDestroyCleanup
|
|
}
|
|
if err := c.SetCgroupItem("cpu.shares", strconv.Itoa(task.Resources.CPU)); err != nil {
|
|
return nil, fmt.Errorf("unable to set cpu shares: %v", err), stopAndDestroyCleanup
|
|
}
|
|
|
|
h := lxcDriverHandle{
|
|
container: c,
|
|
initPid: c.InitPid(),
|
|
lxcPath: lxcPath,
|
|
logger: d.logger,
|
|
killTimeout: GetKillTimeout(task.KillTimeout, d.DriverContext.config.MaxKillTimeout),
|
|
maxKillTimeout: d.DriverContext.config.MaxKillTimeout,
|
|
totalCpuStats: stats.NewCpuStats(),
|
|
userCpuStats: stats.NewCpuStats(),
|
|
systemCpuStats: stats.NewCpuStats(),
|
|
waitCh: make(chan *dstructs.WaitResult, 1),
|
|
doneCh: make(chan bool, 1),
|
|
}
|
|
|
|
go h.run()
|
|
|
|
return &StartResponse{Handle: &h}, nil, noCleanup
|
|
}
|
|
|
|
func (d *LxcDriver) Cleanup(*ExecContext, *CreatedResources) error { return nil }
|
|
|
|
// Open creates the driver to monitor an existing LXC container
|
|
func (d *LxcDriver) Open(ctx *ExecContext, handleID string) (DriverHandle, error) {
|
|
pid := &lxcPID{}
|
|
if err := json.Unmarshal([]byte(handleID), pid); err != nil {
|
|
return nil, fmt.Errorf("Failed to parse handle '%s': %v", handleID, err)
|
|
}
|
|
|
|
var container *lxc.Container
|
|
containers := lxc.Containers(pid.LxcPath)
|
|
for _, c := range containers {
|
|
if c.Name() == pid.ContainerName {
|
|
container = &c
|
|
break
|
|
}
|
|
}
|
|
|
|
if container == nil {
|
|
return nil, fmt.Errorf("container %v not found", pid.ContainerName)
|
|
}
|
|
|
|
handle := lxcDriverHandle{
|
|
container: container,
|
|
initPid: container.InitPid(),
|
|
lxcPath: pid.LxcPath,
|
|
logger: d.logger,
|
|
killTimeout: pid.KillTimeout,
|
|
maxKillTimeout: d.DriverContext.config.MaxKillTimeout,
|
|
totalCpuStats: stats.NewCpuStats(),
|
|
userCpuStats: stats.NewCpuStats(),
|
|
systemCpuStats: stats.NewCpuStats(),
|
|
waitCh: make(chan *dstructs.WaitResult, 1),
|
|
doneCh: make(chan bool, 1),
|
|
}
|
|
go handle.run()
|
|
|
|
return &handle, nil
|
|
}
|
|
|
|
// lxcDriverHandle allows controlling the lifecycle of an lxc container
|
|
type lxcDriverHandle struct {
|
|
container *lxc.Container
|
|
initPid int
|
|
lxcPath string
|
|
|
|
logger *log.Logger
|
|
|
|
killTimeout time.Duration
|
|
maxKillTimeout time.Duration
|
|
|
|
totalCpuStats *stats.CpuStats
|
|
userCpuStats *stats.CpuStats
|
|
systemCpuStats *stats.CpuStats
|
|
|
|
waitCh chan *dstructs.WaitResult
|
|
doneCh chan bool
|
|
}
|
|
|
|
type lxcPID struct {
|
|
ContainerName string
|
|
InitPid int
|
|
LxcPath string
|
|
KillTimeout time.Duration
|
|
}
|
|
|
|
func (h *lxcDriverHandle) ID() string {
|
|
pid := lxcPID{
|
|
ContainerName: h.container.Name(),
|
|
InitPid: h.initPid,
|
|
LxcPath: h.lxcPath,
|
|
KillTimeout: h.killTimeout,
|
|
}
|
|
data, err := json.Marshal(pid)
|
|
if err != nil {
|
|
h.logger.Printf("[ERR] driver.lxc: failed to marshal lxc PID to JSON: %v", err)
|
|
}
|
|
return string(data)
|
|
}
|
|
|
|
func (h *lxcDriverHandle) WaitCh() chan *dstructs.WaitResult {
|
|
return h.waitCh
|
|
}
|
|
|
|
func (h *lxcDriverHandle) Update(task *structs.Task) error {
|
|
h.killTimeout = GetKillTimeout(task.KillTimeout, h.killTimeout)
|
|
return nil
|
|
}
|
|
|
|
func (h *lxcDriverHandle) Exec(ctx context.Context, cmd string, args []string) ([]byte, int, error) {
|
|
return nil, 0, fmt.Errorf("lxc driver cannot execute commands")
|
|
}
|
|
|
|
func (h *lxcDriverHandle) Kill() error {
|
|
name := h.container.Name()
|
|
|
|
h.logger.Printf("[INFO] driver.lxc: shutting down container %q", name)
|
|
if err := h.container.Shutdown(h.killTimeout); err != nil {
|
|
h.logger.Printf("[INFO] driver.lxc: shutting down container %q failed: %v", name, err)
|
|
if err := h.container.Stop(); err != nil {
|
|
h.logger.Printf("[ERR] driver.lxc: error stopping container %q: %v", name, err)
|
|
}
|
|
}
|
|
|
|
close(h.doneCh)
|
|
return nil
|
|
}
|
|
|
|
func (h *lxcDriverHandle) Signal(s os.Signal) error {
|
|
return fmt.Errorf("LXC does not support signals")
|
|
}
|
|
|
|
func (h *lxcDriverHandle) Stats() (*cstructs.TaskResourceUsage, error) {
|
|
cpuStats, err := h.container.CPUStats()
|
|
if err != nil {
|
|
return nil, nil
|
|
}
|
|
total, err := h.container.CPUTime()
|
|
if err != nil {
|
|
return nil, nil
|
|
}
|
|
|
|
t := time.Now()
|
|
|
|
// Get the cpu stats
|
|
system := cpuStats["system"]
|
|
user := cpuStats["user"]
|
|
cs := &cstructs.CpuStats{
|
|
SystemMode: h.systemCpuStats.Percent(float64(system)),
|
|
UserMode: h.systemCpuStats.Percent(float64(user)),
|
|
Percent: h.totalCpuStats.Percent(float64(total)),
|
|
TotalTicks: float64(user + system),
|
|
Measured: LXCMeasuredCpuStats,
|
|
}
|
|
|
|
// Get the Memory Stats
|
|
memData := map[string]uint64{
|
|
"rss": 0,
|
|
"cache": 0,
|
|
"swap": 0,
|
|
}
|
|
rawMemStats := h.container.CgroupItem("memory.stat")
|
|
for _, rawMemStat := range rawMemStats {
|
|
key, val, err := keysToVal(rawMemStat)
|
|
if err != nil {
|
|
h.logger.Printf("[ERR] driver.lxc: error getting stat for line %q", rawMemStat)
|
|
continue
|
|
}
|
|
if _, ok := memData[key]; ok {
|
|
memData[key] = val
|
|
|
|
}
|
|
}
|
|
ms := &cstructs.MemoryStats{
|
|
RSS: memData["rss"],
|
|
Cache: memData["cache"],
|
|
Swap: memData["swap"],
|
|
Measured: LXCMeasuredMemStats,
|
|
}
|
|
|
|
mu := h.container.CgroupItem("memory.max_usage_in_bytes")
|
|
for _, rawMemMaxUsage := range mu {
|
|
val, err := strconv.ParseUint(rawMemMaxUsage, 10, 64)
|
|
if err != nil {
|
|
h.logger.Printf("[ERR] driver.lxc: unable to get max memory usage: %v", err)
|
|
continue
|
|
}
|
|
ms.MaxUsage = val
|
|
}
|
|
ku := h.container.CgroupItem("memory.kmem.usage_in_bytes")
|
|
for _, rawKernelUsage := range ku {
|
|
val, err := strconv.ParseUint(rawKernelUsage, 10, 64)
|
|
if err != nil {
|
|
h.logger.Printf("[ERR] driver.lxc: unable to get kernel memory usage: %v", err)
|
|
continue
|
|
}
|
|
ms.KernelUsage = val
|
|
}
|
|
|
|
mku := h.container.CgroupItem("memory.kmem.max_usage_in_bytes")
|
|
for _, rawMaxKernelUsage := range mku {
|
|
val, err := strconv.ParseUint(rawMaxKernelUsage, 10, 64)
|
|
if err != nil {
|
|
h.logger.Printf("[ERR] driver.lxc: unable to get max kernel memory usage: %v", err)
|
|
continue
|
|
}
|
|
ms.KernelMaxUsage = val
|
|
}
|
|
|
|
taskResUsage := cstructs.TaskResourceUsage{
|
|
ResourceUsage: &cstructs.ResourceUsage{
|
|
CpuStats: cs,
|
|
MemoryStats: ms,
|
|
},
|
|
Timestamp: t.UTC().UnixNano(),
|
|
}
|
|
|
|
return &taskResUsage, nil
|
|
}
|
|
|
|
func (h *lxcDriverHandle) run() {
|
|
defer close(h.waitCh)
|
|
timer := time.NewTimer(containerMonitorIntv)
|
|
for {
|
|
select {
|
|
case <-timer.C:
|
|
process, err := os.FindProcess(h.initPid)
|
|
if err != nil {
|
|
h.waitCh <- &dstructs.WaitResult{Err: err}
|
|
return
|
|
}
|
|
if err := process.Signal(syscall.Signal(0)); err != nil {
|
|
h.waitCh <- &dstructs.WaitResult{}
|
|
return
|
|
}
|
|
timer.Reset(containerMonitorIntv)
|
|
case <-h.doneCh:
|
|
h.waitCh <- &dstructs.WaitResult{}
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func keysToVal(line string) (string, uint64, error) {
|
|
tokens := strings.Split(line, " ")
|
|
if len(tokens) != 2 {
|
|
return "", 0, fmt.Errorf("line isn't a k/v pair")
|
|
}
|
|
key := tokens[0]
|
|
val, err := strconv.ParseUint(tokens[1], 10, 64)
|
|
return key, val, err
|
|
}
|