Add parallel ssh capability

internal/app/wwctl/root.go

@@ -9,9 +9,10 @@ import (
 	"github.com/hpcng/warewulf/internal/app/wwctl/power"
 	"github.com/hpcng/warewulf/internal/app/wwctl/profile"
 	"github.com/hpcng/warewulf/internal/app/wwctl/server"
+	"github.com/hpcng/warewulf/internal/app/wwctl/ssh"
 	"github.com/hpcng/warewulf/internal/app/wwctl/version"
-	"github.com/hpcng/warewulf/internal/pkg/wwlog"
 	"github.com/hpcng/warewulf/internal/pkg/help"
+	"github.com/hpcng/warewulf/internal/pkg/wwlog"
 	"github.com/spf13/cobra"
 	"github.com/spf13/cobra/doc"
 
@@ -21,12 +22,12 @@ import (
 var (
 	rootCmd = &cobra.Command{
 		DisableFlagsInUseLine: true,
-		Use:               "wwctl COMMAND [OPTIONS]",
-		Short:             "Warewulf Control",
-		Long:              "Control interface to the Warewulf Cluster Provisioning System.",
-		PersistentPreRunE: rootPersistentPreRunE,
-		SilenceUsage:      true,
-		SilenceErrors:     true,
+		Use:                   "wwctl COMMAND [OPTIONS]",
+		Short:                 "Warewulf Control",
+		Long:                  "Control interface to the Warewulf Cluster Provisioning System.",
+		PersistentPreRunE:     rootPersistentPreRunE,
+		SilenceUsage:          true,
+		SilenceErrors:         true,
 	}
 	verboseArg bool
 	DebugFlag  bool
@@ -36,8 +37,8 @@ func init() {
 	rootCmd.PersistentFlags().BoolVarP(&verboseArg, "verbose", "v", false, "Run with increased verbosity.")
 	rootCmd.PersistentFlags().BoolVarP(&DebugFlag, "debug", "d", false, "Run with debugging messages enabled.")
 
-        rootCmd.SetUsageTemplate(help.UsageTemplate)
-        rootCmd.SetHelpTemplate(help.HelpTemplate)
+	rootCmd.SetUsageTemplate(help.UsageTemplate)
+	rootCmd.SetHelpTemplate(help.HelpTemplate)
 
 	rootCmd.AddCommand(overlay.GetCommand())
 	rootCmd.AddCommand(container.GetCommand())
@@ -48,7 +49,7 @@ func init() {
 	rootCmd.AddCommand(configure.GetCommand())
 	rootCmd.AddCommand(server.GetCommand())
 	rootCmd.AddCommand(version.GetCommand())
-
+	rootCmd.AddCommand(ssh.GetCommand())
 }
 
 // GetRootCommand returns the root cobra.Command for the application.

internal/app/wwctl/ssh/main.go

@@ -0,0 +1,89 @@
+package ssh
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"os"
+	"os/exec"
+	"time"
+
+	"github.com/hpcng/warewulf/internal/pkg/batch"
+	"github.com/hpcng/warewulf/internal/pkg/node"
+	"github.com/hpcng/warewulf/internal/pkg/wwlog"
+	"github.com/hpcng/warewulf/pkg/hostlist"
+	"github.com/spf13/cobra"
+)
+
+func CobraRunE(cmd *cobra.Command, args []string) error {
+	batchpool := batch.New(FanOut)
+
+	nodeDB, err := node.New()
+	if err != nil {
+		wwlog.Printf(wwlog.ERROR, "Could not open node configuration: %s\n", err)
+		os.Exit(1)
+	}
+
+	nodes, err := nodeDB.FindAllNodes()
+	if err != nil {
+		wwlog.Printf(wwlog.ERROR, "Could not get node list: %s\n", err)
+		os.Exit(1)
+	}
+
+	if len(args) > 0 {
+		nodes = node.FilterByName(nodes, hostlist.Expand(args))
+	} else {
+		//nolint:errcheck
+		cmd.Usage()
+		os.Exit(1)
+	}
+
+	for _, node := range nodes {
+
+		if _, ok := node.NetDevs["default"]; !ok {
+			fmt.Fprintf(os.Stderr, "%s: Default network device doesn't exist\n", node.Id.Get())
+			continue
+		}
+
+		if node.NetDevs["default"].Ipaddr.Get() == "" {
+			fmt.Fprintf(os.Stderr, "%s: Default network IP address not configured\n", node.Id.Get())
+			continue
+		}
+
+		nodename := node.Id.Print()
+		var command []string
+
+		command = append(command, node.NetDevs["default"].Ipaddr.Get())
+		command = append(command, args[1:]...)
+
+		batchpool.Submit(func() {
+
+			wwlog.Printf(wwlog.DEBUG, "Sending command to node '%s': %s\n", nodename, command)
+			var stdout, stderr bytes.Buffer
+			cmd := exec.Command(SshPath, command...)
+			cmd.Stdin = os.Stdin
+			cmd.Stdout = &stdout
+			cmd.Stderr = &stderr
+			_ = cmd.Run()
+
+			scan_stdout := bufio.NewScanner(&stdout)
+			for scan_stdout.Scan() {
+				fmt.Printf("%s: %s\n", nodename, scan_stdout.Text())
+			}
+
+			scan_stderr := bufio.NewScanner(&stderr)
+			for scan_stderr.Scan() {
+				fmt.Fprintf(os.Stderr, "%s: %s\n", nodename, scan_stderr.Text())
+			}
+
+			//util.ExecInteractive(SshPath, command...)
+			time.Sleep(time.Duration(Sleep) * time.Second)
+
+		})
+
+	}
+
+	batchpool.Run()
+
+	return nil
+}

internal/app/wwctl/ssh/root.go

@@ -0,0 +1,31 @@
+package ssh
+
+import (
+	"github.com/spf13/cobra"
+)
+
+var (
+	baseCmd = &cobra.Command{
+		DisableFlagsInUseLine: true,
+		Use:                   "ssh [OPTIONS] NODE_PATTERN...",
+		Short:                 "SSH into configured nodes in parallel",
+		Long:                  "Easily ssh into nodes in parallel to run non-interactive commands\n",
+		RunE:                  CobraRunE,
+	}
+	Show    bool
+	FanOut  int
+	Sleep   int
+	SshPath string
+)
+
+func init() {
+	baseCmd.PersistentFlags().BoolVarP(&Show, "dryrun", "n", false, "Show commands to run")
+	baseCmd.PersistentFlags().IntVarP(&FanOut, "fanout", "f", 32, "How many connections to run in parallel")
+	baseCmd.PersistentFlags().IntVarP(&Sleep, "sleep", "s", 0, "Seconds to sleep inbetween processes")
+	baseCmd.PersistentFlags().StringVar(&SshPath, "rsh", "/usr/bin/ssh", "Path to use for RSH/SSH command")
+}
+
+// GetRootCommand returns the root cobra.Command for the application.
+func GetCommand() *cobra.Command {
+	return baseCmd
+}