add cluster reroute commands, fix usage width bug (#59)

fixes #36

README.md

@@ -433,6 +433,40 @@ $ esctl search -i hyperdrive -l 2 | jq
 }
 ```
 
+There are also some uniq features which are not directly available via
+the ES API or GUI. Here's one example: say you have a number of
+indices with ILM policies each. At some day there were a surge in
+incoming data in some of them and you want to know, when the excess
+data will be rolled over to cold storage:
+
+```console
+$ esctl ilm forecast sh -f warm -w 3d 
+1.1 TB bytes of data in warm phase will be rolled within 72h0m0s to the next phase
+```
+
+You may also look at a detailed ilm forecast list:
+
+```console
+$ esctl ilm forecast ls -f warm -w 3d
+INDEX                           CURRENT-SIZE  CURRENT-AGE  VIRTUAL-AGE  MIN-AGE  MIN-SIZE  CURRENT-PHASE  NEXT-PHASE
+foobar-n1-p01-elastic-000126    12 GB         2d:8h:12m    3d:5h:16m    7d       25 GB     hot            warm      
+foobar-n1-p01-misc-000070       16 GB         5d:16h:31m   4d:10h:31m   7d       25 GB     hot            warm      
+foobar-n1-q01-elastic-000122    23 GB         5d:0h:11m    6d:10h:33m   7d       25 GB     hot            warm      
+foobar-n1-q01-misc-000072       18 GB         6d:15h:21m   4d:21h:36m   7d       25 GB     hot            warm      
+delaware-f1-p01-kafka-000023    1.3 MB        15h:12m      0s           7d       25 GB     hot            warm      
+delaware-f1-p01-misc-000024     17 GB         6d:16h:1m    4d:16h:33m   7d       25 GB     hot            warm      
+delaware-f1-q01-kafka-000023    1.5 MB        15h:12m      0s           7d       25 GB     hot            warm      
+delaware-f1-q01-misc-000024     16 GB         6d:15h:31m   4d:13h:52m   7d       25 GB     hot            warm      
+delaware-n1-p01-elastic-000417  16 GB         12h:42m      4d:10h:31m   7d       25 GB     hot            warm 
+```
+So you can see, which index will be rolled over when. Note the
+**VIRTUAL-AGE** field however: it is calculated from the current
+storage usage of the index in relation to rollover max shard size. So
+you can see, when an index will be rolled over either because it aged
+out or because its storage exceeded the limit.
+
+---
+
 Please note, that `esctl` is still in its early stages and things are
 changing heavily every now and then. New commands are being added
 constantly as well.
@@ -440,95 +474,99 @@ constantly as well.
 ### Command tree:
 
 ```console
-api                   - api access and documentation
-  list                - list index of API calls
-  show                - show an API doc
-  repl                - interactive API repl
-ccr                   - manage cross cluster replication
-  status              - cross cluster replication status (yaml config with 2 clusters required)
-  pause               - pause shard allocation
-  resume              - resume shard allocation
-  follower            - manage ccr follower indices
-    show              - show ccr follower index details
-    add               - add ccr follower index
-    delete            - delete ccr follower index
-    unfollow          - unfollow ccr follower index
-    pause             - pause ccr index to follow
-    resume            - resume ccr index to follow
-    renew             - renew ccr follower index
-  info                - show ccr remote info
-cluster               - manage cluster[s]
-  status              - show cluster status
-  switch              - set current elasticsearch cluster
-  list                - list configured clusters
-  settings            - cluster settings management
-    list              - show cluster settings
-    set               - set|update cluster settings
-datastream            - manage data streams
-  list                - list indicies
-  show                - show details about an data stream
-  create              - create a new data stream
-  delete              - delete a data stream
-  rollover            - roll over a data stream
-doc                   - manage documents
-  add                 - add JSON document index
-  show                - show a JSON document
-  delete              - delete JSON document[s] from index[es]
-ilm                   - manage index lifecycle
-  retry               - retry applying an ILM profile to an index
-  status              - get the current index lifecycle management status
-  list                - list index lifecycle policies
-  show                - show details about an index lifecycle policy
-  create              - create a index lifecycle policy
-  forecast            - calculate index phase movements
-    list              - list index rollover config
-    show              - show rollover forecast over all indices
-index                 - manage indicies
-  list                - list indicies
-  show                - show details about an index
-  create              - create a new index
-  modify              - modify anindex
-  delete              - delete an index
-  close               - close an index
-  allocation          - explain index allocation
-  fields              - show info about field capabilities
-  ilm                 - show ilm status
-  alias               - manage index aliases
-    create            - create an index alias
-    list              - list index aliases
-    delete            - delete an index alias
-    rollover          - roll over an index alias
-  template            - manage index templates
-    list              - list index templates
-    show              - show details about an index template
-    create            - create a new index template
-    modify            - modify a new index template
-    delete            - delete an index template
-node                  - manage nodes
-  list                - list nodes
-  show                - show details about a node
-role                  - manage roles
-  list                - list roles
-  show                - show details about a role
-  diff                - show differences between roles and CSV baseline
-search                - search within an index
-shard                 - manage shards
-  list                - list shards
-  show                - show details about a shard
-snapshot              - manage snapshots
-  list                - list snapshots
-  show                - show details about a snapshot
-task                  - manage tasks
-  list                - list tasks
-  cancel              - cancel running task
-version               - show esctl version information
-debug                 - developer only
-help-jsonpath         - show jsonpath help
-completion            - Output shell completion script for bash, zsh, fish, or Powershell
-  pwsh                - Output pwsh completion script
-  bash                - Output bash completion script
-  zsh                 - Output zsh completion script
-  fish                - Output fish completion script
+api                         - api access and documentation
+  list                      - list index of API calls
+  show                      - show an API doc
+  repl                      - interactive API repl
+ccr                         - manage cross cluster replication
+  status                    - cross cluster replication status (yaml config with 2 clusters required)
+  pause                     - pause shard allocation
+  resume                    - resume shard allocation
+  follower                  - manage ccr follower indices
+    show                    - show ccr follower index details
+    add                     - add ccr follower index
+    delete                  - delete ccr follower index
+    unfollow                - unfollow ccr follower index
+    pause                   - pause ccr index to follow
+    resume                  - resume ccr index to follow
+    renew                   - renew ccr follower index
+  info                      - show ccr remote info
+cluster                     - manage cluster[s]
+  status                    - show cluster status
+  switch                    - set current elasticsearch cluster
+  list                      - list configured clusters
+  settings                  - cluster settings management
+    list                    - show cluster settings
+    set                     - set|update cluster settings
+  reroute                   - manually change the allocation of individual shards in the cluster.
+    move                    - move shard to another node
+    allocate-replica        - allocate-replica replica to another node
+    cancel                  - cancel a reroute operation
+    allocate-empty-primary  - allocate an empty primary shard to a node
+    allocate-stale-primary  - allocate a stale primary shard to a node
+datastream                  - manage data streams
+  list                      - list indicies
+  show                      - show details about an data stream
+  create                    - create a new data stream
+  delete                    - delete a data stream
+  rollover                  - roll over a data stream
+doc                         - manage documents
+  add                       - add JSON document index
+  show                      - show a JSON document
+  delete                    - delete JSON document[s] from index[es]
+ilm                         - manage index lifecycle
+  retry                     - retry applying an ILM profile to an index
+  status                    - get the current index lifecycle management status
+  list                      - list index lifecycle policies
+  show                      - show details about an index lifecycle policy
+  create                    - create a new lifecycle policy
+  update                    - update an lifecycle policy
+  forecast                  - calculate index phase movements
+    list                    - list index rollover config
+    show                    - show rollover forecast over all indices
+  explain                   - explain ilm condition of an index
+index                       - manage indicies
+  list                      - list indicies
+  show                      - show details about an index
+  create                    - create a new index
+  update                    - update an index
+  delete                    - delete an index
+  close                     - close an index
+  allocation                - explain index allocation
+  fields                    - show info about field capabilities
+  ilm                       - show ilm status
+  alias                     - manage index aliases
+    create                  - create an index alias
+    list                    - list index aliases
+    delete                  - delete an index alias
+    rollover                - roll over an index alias
+  template                  - manage index templates
+    list                    - list index templates
+    show                    - show details about an index template
+    create                  - create a new index template
+    update                  - update a new index template
+    delete                  - delete an index template
+node                        - manage nodes
+  list                      - list nodes
+  show                      - show details about a node
+role                        - manage roles
+  list                      - list roles
+  show                      - show details about a role
+  diff                      - show differences between roles and CSV baseline
+search                      - search within an index
+shard                       - manage shards
+  list                      - list shards
+  show                      - show details about a shard
+snapshot                    - manage snapshots
+  list                      - list snapshots
+  show                      - show details about a snapshot
+task                        - manage tasks
+  list                      - list tasks
+  cancel                    - cancel running task
+version                     - show esctl version information
+debug                       - developer only
+help-jsonpath               - show jsonpath help
+help-command-overview       - show overview of all available commands
 ```
 
 # Development

cmd/cluster.go

@@ -37,6 +37,7 @@ func Cluster(conf *cfg.Config) *cli.Command {
 			ClusterSwitch(conf),
 			ClusterList(conf),
 			ClusterSettings(conf),
+			ClusterReroute(conf),
 		},
 	}
 }

cmd/cluster_reroute.go

@@ -0,0 +1,225 @@
+/*
+Copyright © 2026 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+package cmd
+
+import (
+	"context"
+	"errors"
+
+	"codeberg.org/scip/esctl/pkg/cfg"
+	"codeberg.org/scip/esctl/pkg/es"
+
+	"github.com/urfave/cli/v3"
+)
+
+func ClusterReroute(conf *cfg.Config) *cli.Command {
+	return &cli.Command{
+		Name:      "reroute",
+		Usage:     "manually change the allocation of individual shards in the cluster.",
+		UsageText: "reroute <cluster-name>",
+		Aliases:   []string{"ctx"},
+
+		Commands: []*cli.Command{
+			ClusterRerouteMove(conf),
+			ClusterRerouteAllocateReplica(conf),
+			ClusterRerouteCancel(conf),
+			ClusterRerouteAllocatePrimary(conf, false),
+			ClusterRerouteAllocatePrimary(conf, true),
+		},
+	}
+}
+
+func ClusterRerouteMove(conf *cfg.Config) *cli.Command {
+	return &cli.Command{
+		Name:      "move",
+		Usage:     "move shard to another node",
+		UsageText: "move [options] <index>",
+
+		ShellComplete: func(ctx context.Context, cmd *cli.Command) {
+			complete(cmd, Cindex)
+		},
+
+		Flags: []cli.Flag{
+			&cli.IntFlag{
+				Name:        "shard",
+				Usage:       "shard to move",
+				Destination: &conf.Shards,
+				Aliases:     []string{"s"},
+				Required:    true,
+			},
+			&cli.StringFlag{
+				Name:        "from-node",
+				Usage:       "current node",
+				Destination: &conf.FromNode,
+				Aliases:     []string{"f"},
+				Required:    true,
+			},
+			&cli.StringFlag{
+				Name:        "to-node",
+				Usage:       "node to move to",
+				Destination: &conf.ToNode,
+				Aliases:     []string{"t"},
+				Required:    true,
+			},
+		},
+
+		Action: func(ctx context.Context, cmd *cli.Command) error {
+			index := cmd.Args().Get(0)
+			if index == "" {
+				return errors.New("no index specified")
+			}
+
+			return es.ClusterRerouteMove(conf, index)
+		},
+	}
+}
+
+func ClusterRerouteAllocateReplica(conf *cfg.Config) *cli.Command {
+	return &cli.Command{
+		Name:      "allocate-replica",
+		Usage:     "allocate-replica replica to another node",
+		UsageText: "allocate-replica [options] <index>",
+
+		ShellComplete: func(ctx context.Context, cmd *cli.Command) {
+			complete(cmd, Cindex)
+		},
+
+		Flags: []cli.Flag{
+			&cli.IntFlag{
+				Name:        "shard",
+				Usage:       "shard to move",
+				Destination: &conf.Shards,
+				Aliases:     []string{"s"},
+				Required:    true,
+			},
+			&cli.StringFlag{
+				Name:        "to-node",
+				Usage:       "node to move to",
+				Destination: &conf.ToNode,
+				Aliases:     []string{"t"},
+				Required:    true,
+			},
+		},
+
+		Action: func(ctx context.Context, cmd *cli.Command) error {
+			index := cmd.Args().Get(0)
+			if index == "" {
+				return errors.New("no index specified")
+			}
+
+			return es.ClusterRerouteAllocateReplica(conf, index)
+		},
+	}
+}
+
+func ClusterRerouteCancel(conf *cfg.Config) *cli.Command {
+	return &cli.Command{
+		Name:      "cancel",
+		Usage:     "cancel a reroute operation",
+		UsageText: "cancel [options] <index>",
+
+		ShellComplete: func(ctx context.Context, cmd *cli.Command) {
+			complete(cmd, Cindex)
+		},
+
+		Flags: []cli.Flag{
+			&cli.IntFlag{
+				Name:        "shard",
+				Usage:       "shard to move",
+				Destination: &conf.Shards,
+				Aliases:     []string{"s"},
+				Required:    true,
+			},
+			&cli.StringFlag{
+				Name:        "to-node",
+				Usage:       "node to move to",
+				Destination: &conf.ToNode,
+				Aliases:     []string{"t"},
+				Required:    true,
+			},
+			&cli.BoolFlag{
+				Name:        "allow-primary",
+				Usage:       "allow primary shard to cancel",
+				Destination: &conf.AllowPrimary,
+				Aliases:     []string{"a"},
+			},
+		},
+
+		Action: func(ctx context.Context, cmd *cli.Command) error {
+			index := cmd.Args().Get(0)
+			if index == "" {
+				return errors.New("no index specified")
+			}
+
+			return es.ClusterRerouteCancel(conf, index)
+		},
+	}
+}
+
+func ClusterRerouteAllocatePrimary(conf *cfg.Config, stale bool) *cli.Command {
+	name := "allocate-empty-primary"
+	usage := "allocate an empty primary shard to a node"
+
+	if stale {
+		name = "allocate-stale-primary"
+		usage = "allocate a stale primary shard to a node"
+
+	}
+
+	return &cli.Command{
+		Name:      name,
+		Usage:     usage,
+		UsageText: name + " [options] <index>",
+
+		ShellComplete: func(ctx context.Context, cmd *cli.Command) {
+			complete(cmd, Cindex)
+		},
+
+		Flags: []cli.Flag{
+			&cli.IntFlag{
+				Name:        "shard",
+				Usage:       "shard to move",
+				Destination: &conf.Shards,
+				Aliases:     []string{"s"},
+				Required:    true,
+			},
+			&cli.StringFlag{
+				Name:        "to-node",
+				Usage:       "node to move to",
+				Destination: &conf.ToNode,
+				Aliases:     []string{"t"},
+				Required:    true,
+			},
+			&cli.BoolFlag{
+				Name:        "accept-data-loss",
+				Usage:       "",
+				Destination: &conf.AcceptDataLoss,
+				Aliases:     []string{"a"},
+				Required:    true,
+			},
+		},
+
+		Action: func(ctx context.Context, cmd *cli.Command) error {
+			index := cmd.Args().Get(0)
+			if index == "" {
+				return errors.New("no index specified")
+			}
+
+			return es.ClusterRerouteAllocatePrimary(conf, index, stale)
+		},
+	}
+}

cmd/ilm.go

@@ -36,7 +36,8 @@ func Ilm(conf *cfg.Config) *cli.Command {
 			IlmStatus(conf),
 			IlmList(conf),
 			IlmShow(conf),
-			IlmCreate(conf),
+			IlmCreate(conf, false),
+			IlmCreate(conf, true),
 			IlmForecast(conf),
 			IlmExplain(conf),
 		},
@@ -103,6 +104,15 @@ func IlmShow(conf *cfg.Config) *cli.Command {
 		Usage:     "show details about an index lifecycle policy",
 		UsageText: "show <policy>",
 
+		Flags: []cli.Flag{
+			&cli.BoolFlag{
+				Name:        "tree",
+				Usage:       "display policy as a tree",
+				Destination: &conf.Ilm.Tree,
+				Aliases:     []string{"t"},
+			},
+		},
+
 		Action: func(ctx context.Context, cmd *cli.Command) error {
 			policy := cmd.Args().Get(0)
 			if policy == "" {
@@ -118,12 +128,22 @@ func IlmShow(conf *cfg.Config) *cli.Command {
 	}
 }
 
-func IlmCreate(conf *cfg.Config) *cli.Command {
+func IlmCreate(conf *cfg.Config, modify bool) *cli.Command {
+	name := "create"
+	alias := "+"
+	usage := "create a new lifecycle policy"
+
+	if modify {
+		name = "update"
+		usage = "update an lifecycle policy"
+		alias = "upd"
+	}
+
 	return &cli.Command{
-		Name:      "create",
-		Aliases:   []string{"+"},
-		Usage:     "create a index lifecycle policy",
-		UsageText: "create [options] <policy>",
+		Name:      name,
+		Aliases:   []string{alias},
+		Usage:     usage,
+		UsageText: name + " [options] <policy>",
 
 		Flags: []cli.Flag{
 			&cli.StringFlag{

cmd/index.go

@@ -154,8 +154,8 @@ func IndexCreate(conf *cfg.Config, modify bool) *cli.Command {
 	usage := "create a new index"
 
 	if modify {
-		name = "modify"
-		usage = "modify anindex"
+		name = "update"
+		usage = "update an index"
 	}
 
 	return &cli.Command{

cmd/index_template.go

@@ -83,8 +83,8 @@ func IndexTemplateCreate(conf *cfg.Config, modify bool) *cli.Command {
 	required := true
 
 	if modify {
-		name = "modify"
-		alias = "mod"
+		name = "update"
+		alias = "upd"
 		required = false
 	}
 

cmd/root.go

@@ -42,7 +42,6 @@ func Finish(err error) int {
 
 func Main() int {
 	conf := cfg.NewConfig()
-	tree := false
 
 	cmd := &cli.Command{
 		Name:                  "esctl",
@@ -64,13 +63,6 @@ func Main() int {
 				Usage:       "enable HTTP debugging",
 				Destination: &conf.DebugHTTP,
 			},
-			&cli.BoolFlag{
-				Name:        "show-command-tree",
-				Value:       false,
-				Usage:       "generate a command tree",
-				Destination: &tree,
-				Hidden:      true,
-			},
 			&cli.BoolFlag{
 				Name:        "align-ints",
 				Aliases:     []string{"I"},
@@ -125,17 +117,10 @@ func Main() int {
 			Version(conf),
 			Debug(conf),
 			HelpJsonPath(conf),
+			HelpUsage(conf),
 		},
 
 		Before: func(ctx context.Context, cmd *cli.Command) (context.Context, error) {
-			if tree {
-				if err := Tree(cmd); err != nil {
-					return nil, err
-				}
-
-				os.Exit(0)
-			}
-
 			if err := conf.Init(); err != nil {
 				if len(os.Args) > 1 {
 					return nil, err
@@ -261,22 +246,81 @@ func Debug(conf *cfg.Config) *cli.Command {
 	}
 }
 
-func Tree(cmd *cli.Command) error {
-	max := 20
+func HelpUsage(conf *cfg.Config) *cli.Command {
+	return &cli.Command{
+		Name:    "help-command-overview",
+		Usage:   "show overview of all available commands",
+		Aliases: []string{"usage"},
 
-	return cmd.Walk(func(cmd *cli.Command) error {
-		path := cmd.Path()
-		command := path[len(path)-1]
+		Flags: []cli.Flag{
+			&cli.BoolFlag{
+				Name:        "hidden",
+				Usage:       "include hidden commands",
+				Destination: &conf.Hidden,
+				Aliases:     []string{"H"},
+			},
+		},
 
-		if len(path) == 1 || command == "help" {
-			return nil
-		}
+		Action: func(ctx context.Context, cmd *cli.Command) error {
+			maxCommandWidth := 0
 
-		indent := strings.Repeat("  ", len(path[1:])-1)
-		space := strings.Repeat(" ", max-(len(command)+len(indent)))
+			// first pass, determine max command width
+			if err := walkVisible(conf, cmd.Root(), func(cmd *cli.Command) error {
+				path := cmd.Path()
+				size := len(path[len(path)-1])
 
-		fmt.Printf("%s%s %s - %s\n", indent, command, space, cmd.Usage)
+				if size > maxCommandWidth {
+					maxCommandWidth = size
+				}
+
+				return nil
+			}); err != nil {
+				return err
+			}
+
+			maxCommandWidth += 4 // account for indent width
+
+			// second pass, build tree
+			return walkVisible(conf, cmd.Root(), func(cmd *cli.Command) error {
+				path := cmd.Path()
+				command := path[len(path)-1]
+
+				if len(path) == 1 || command == "help" {
+					return nil
+				}
+
+				indent := strings.Repeat("  ", len(path[1:])-1)
+				space := strings.Repeat(" ", maxCommandWidth-(len(command)+len(indent)))
+
+				fmt.Printf("%s%s %s - %s\n", indent, command, space, cmd.Usage)
+
+				return nil
+			})
+		},
+	}
 
-		return nil
-	})
+}
+
+// copy of cmd.Walk() with the exception to skip hidden commands and its siblings
+// see: https://github.com/urfave/cli/issues/2372
+func walkVisible(conf *cfg.Config, cmd *cli.Command, fn func(*cli.Command) error) error {
+	if fn == nil {
+		return nil
+	}
+
+	if !conf.Hidden && cmd.Hidden {
+		return nil
+	}
+
+	if err := fn(cmd); err != nil {
+		return err
+	}
+
+	for _, sub := range cmd.Commands {
+		if err := walkVisible(conf, sub, fn); err != nil {
+			return err
+		}
+	}
+
+	return nil
 }

pkg/cfg/config.go

@@ -28,7 +28,7 @@ import (
 )
 
 const (
-	Version string = `v0.0.22`
+	Version string = `v0.0.23`
 )
 
 var (
@@ -103,6 +103,9 @@ type Config struct {
 	Tag string // api ls: -t
 
 	Ilm Ilm // ilm create
+
+	FromNode, ToNode             string // cluster reroute move: -f + -t
+	AllowPrimary, AcceptDataLoss bool   // cluster reroute cancel: -p,-a
 }
 
 func NewConfig() *Config {

pkg/cfg/ilm.go

@@ -42,6 +42,7 @@ type Ilm struct {
 	DeleteSearchableSnapshots bool
 
 	MinAge, FromPhase, Within string // forecast
+	Tree                      bool
 }
 
 func (cfg *Ilm) HaveHot() bool {

pkg/es/cluster_reroute.go

@@ -0,0 +1,125 @@
+/*
+Copyright © 2026 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+package es
+
+import (
+	"context"
+	"fmt"
+
+	"codeberg.org/scip/esctl/pkg/cfg"
+	"github.com/elastic/go-elasticsearch/v9/typedapi/esdsl"
+	"github.com/elastic/go-elasticsearch/v9/typedapi/types"
+)
+
+func ClusterRerouteMove(conf *cfg.Config, index string) error {
+	move := conf.DefaultCluster.ES().Cluster.Reroute()
+
+	commands := esdsl.NewCommand()
+	moveCommand := &types.CommandMoveAction{
+		Shard:    conf.Shards,
+		FromNode: conf.FromNode,
+		ToNode:   conf.ToNode,
+		Index:    index,
+	}
+
+	commands.CommandCaster().Move = moveCommand
+
+	move.Commands(commands)
+
+	_, err := move.Do(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed to reroute move: %w", err)
+	}
+
+	return nil
+}
+
+func ClusterRerouteAllocateReplica(conf *cfg.Config, index string) error {
+	move := conf.DefaultCluster.ES().Cluster.Reroute()
+
+	commands := esdsl.NewCommand()
+	allocCommand := &types.CommandAllocateReplicaAction{
+		Shard: conf.Shards,
+		Node:  conf.ToNode,
+		Index: index,
+	}
+
+	commands.CommandCaster().AllocateReplica = allocCommand
+
+	move.Commands(commands)
+
+	_, err := move.Do(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed to allocate a replica shard: %w", err)
+	}
+
+	return nil
+}
+
+func ClusterRerouteCancel(conf *cfg.Config, index string) error {
+	move := conf.DefaultCluster.ES().Cluster.Reroute()
+
+	commands := esdsl.NewCommand()
+	cancelCommand := &types.CommandCancelAction{
+		Shard:        conf.Shards,
+		Node:         conf.ToNode,
+		Index:        index,
+		AllowPrimary: &conf.AllowPrimary,
+	}
+
+	commands.CommandCaster().Cancel = cancelCommand
+
+	move.Commands(commands)
+
+	_, err := move.Do(context.Background())
+	if err != nil {
+		return fmt.Errorf("failed to cancel a reroute process: %w", err)
+	}
+
+	return nil
+}
+
+func ClusterRerouteAllocatePrimary(conf *cfg.Config, index string, stale bool) error {
+	move := conf.DefaultCluster.ES().Cluster.Reroute()
+
+	commands := esdsl.NewCommand()
+	allocCommand := &types.CommandAllocatePrimaryAction{
+		Shard:          conf.Shards,
+		Node:           conf.ToNode,
+		Index:          index,
+		AcceptDataLoss: conf.AcceptDataLoss,
+	}
+
+	if stale {
+		commands.CommandCaster().AllocateStalePrimary = allocCommand
+	} else {
+		commands.CommandCaster().AllocateEmptyPrimary = allocCommand
+	}
+
+	move.Commands(commands)
+
+	_, err := move.Do(context.Background())
+	if err != nil {
+		which := "empty"
+		if stale {
+			which = "stale"
+		}
+		return fmt.Errorf("failed to allocate %s primary shard: %w", which, err)
+	}
+
+	return nil
+}

pkg/es/ilm.go

@@ -121,6 +121,10 @@ func IlmShow(conf *cfg.Config, policy string) error {
 		return errors.New("no ilm policy retrieved")
 	}
 
+	if conf.Ilm.Tree {
+		return IlmShowTree(conf, ilm.Policy)
+	}
+
 	table := printer.NewTable(conf, 2, 5)
 	table.Addheaders("ilm policy setting", "value")
 
@@ -135,6 +139,101 @@ func IlmShow(conf *cfg.Config, policy string) error {
 	return table.Print()
 }
 
+// Visualize  phases or  a ILM  policy, taking  into account  that the
+// minAge for the current phases is set in the next phase
+func IlmShowTree(conf *cfg.Config, ilm types.IlmPolicy) error {
+	indent := ""
+
+	table := printer.NewTable(conf, 4, 0)
+	table.Addheaders("phase", "min age", "min size", "snapshot repo")
+
+	for _, phase := range IlmPhaseOrder {
+		if phase == "hot" {
+			fmt.Printf("%s%s phase:\n%s      rollover after %s\n",
+				indent, phase,
+				indent, formatDuration(parseDuration(ilm.Phases.Hot.Actions.Rollover.MaxAge.(string))),
+			)
+
+			if ilm.Phases.Hot.Actions.Rollover.MaxPrimaryShardSize != "" {
+				fmt.Printf("%s      rollover when storage > %s\n",
+					indent, ilm.Phases.Hot.Actions.Rollover.MaxPrimaryShardSize)
+			}
+
+			if ilm.Phases.Hot.Actions.Rollover.MaxDocs != nil {
+				fmt.Printf("%s      rollover docs > %d\n",
+					indent, *ilm.Phases.Hot.Actions.Rollover.MaxDocs)
+			}
+
+			indent += "    "
+			continue
+		}
+
+		current := getIlmCurrentPhase(ilm, phase)
+
+		if current == nil {
+			continue
+		}
+
+		next := findNextPhase(ilm, phase)
+
+		fmt.Printf("%s%s phase:\n", indent, phase)
+
+		if next != nil {
+			fmt.Printf("%s      rollover after %s\n",
+				indent, formatDuration(next.minage),
+			)
+
+			if current.Actions.SearchableSnapshot != nil {
+				fmt.Printf("%s      roll to snapshot repo: %s\n",
+					indent, current.Actions.SearchableSnapshot.SnapshotRepository)
+			}
+
+			if current.Actions.Forcemerge != nil {
+				fmt.Printf("%s      force merge segments: %d\n",
+					indent, current.Actions.Forcemerge.MaxNumSegments)
+			}
+
+			if current.Actions.Shrink != nil {
+				fmt.Printf("%s      shrink shards: %d\n",
+					indent, *current.Actions.Shrink.NumberOfShards)
+			}
+
+			if current.Actions.SetPriority != nil {
+				fmt.Printf("%s      priority: %d\n",
+					indent, *current.Actions.SetPriority.Priority)
+			}
+
+			if current.Actions.Delete != nil && current.Actions.Delete.DeleteSearchableSnapshot != nil {
+				fmt.Printf("%s      delete searchable snapshots: %t\n",
+					indent, *current.Actions.Delete.DeleteSearchableSnapshot)
+			}
+		}
+
+		if phase == "delete" {
+			fmt.Printf("%s      delete immediately\n", indent)
+		}
+
+		indent += "    "
+	}
+
+	return nil
+}
+
+func getIlmCurrentPhase(policy types.IlmPolicy, currentPhase string) *types.Phase {
+	switch currentPhase {
+	case "hot":
+		return policy.Phases.Hot
+	case "warm":
+		return policy.Phases.Warm
+	case "cold":
+		return policy.Phases.Cold
+	case "frozen":
+		return policy.Phases.Frozen
+	default:
+		return policy.Phases.Delete
+	}
+}
+
 func ilmPhaseString(phase *types.Phase, short bool) string {
 	if phase == nil {
 		return ""
@@ -220,6 +319,24 @@ func IlmExplain(conf *cfg.Config, index string) error {
 }
 
 func IlmCreate(conf *cfg.Config, policyname string) error {
+	var policy *types.IlmPolicy = nil
+
+	res, err := conf.DefaultCluster.ES().Ilm.GetLifecycle().
+		Policy(policyname).
+		Do(context.Background())
+	if err == nil {
+		if conf.Debug {
+			repr.Println(res)
+		}
+
+		ilm, exists := res[policyname]
+		if !exists {
+			return errors.New("no ilm policy retrieved")
+		}
+
+		policy = &ilm.Policy
+	}
+
 	ilm := conf.DefaultCluster.ES().Ilm.PutLifecycle(policyname)
 	cfg := conf.Ilm
 
@@ -231,6 +348,16 @@ func IlmCreate(conf *cfg.Config, policyname string) error {
 		rollover := &types.RolloverAction{}
 		haveroll := false
 
+		if policy != nil {
+			// update
+			actions = policy.Phases.Hot.Actions
+
+			if policy.Phases.Hot.Actions.Rollover != nil {
+				rollover = policy.Phases.Hot.Actions.Rollover
+				haveroll = true
+			}
+		}
+
 		if cfg.HotMinAge != "" {
 			hot.MinAge = cfg.HotMinAge
 		}
@@ -255,12 +382,22 @@ func IlmCreate(conf *cfg.Config, policyname string) error {
 
 		hot.Actions = actions.IlmActionsCaster()
 		phases.PhasesCaster().Hot = &hot
+	} else {
+		if policy != nil {
+			// update
+			phases.PhasesCaster().Hot = policy.Phases.Hot
+		}
 	}
 
 	if cfg.HaveWarm() {
 		warm := types.Phase{}
 		var actions types.IlmActionsVariant = esdsl.NewIlmActions()
 
+		if policy != nil {
+			// update
+			actions = policy.Phases.Warm.Actions
+		}
+
 		if cfg.WarmForceMerge != 0 {
 			actions.IlmActionsCaster().Forcemerge = &types.ForceMergeAction{MaxNumSegments: cfg.WarmForceMerge}
 		}
@@ -279,12 +416,22 @@ func IlmCreate(conf *cfg.Config, policyname string) error {
 
 		warm.Actions = actions.IlmActionsCaster()
 		phases.PhasesCaster().Warm = &warm
+	} else {
+		if policy != nil && policy.Phases.Warm != nil {
+			// update
+			phases.PhasesCaster().Warm = policy.Phases.Warm
+		}
 	}
 
 	if cfg.HaveCold() {
 		cold := types.Phase{}
 		var actions types.IlmActionsVariant = esdsl.NewIlmActions()
 
+		if policy != nil {
+			// update
+			actions = policy.Phases.Cold.Actions
+		}
+
 		if cfg.ColdForceMerge != 0 {
 			actions.IlmActionsCaster().Forcemerge = &types.ForceMergeAction{MaxNumSegments: cfg.ColdForceMerge}
 		}
@@ -304,12 +451,22 @@ func IlmCreate(conf *cfg.Config, policyname string) error {
 
 		cold.Actions = actions.IlmActionsCaster()
 		phases.PhasesCaster().Cold = &cold
+	} else {
+		if policy != nil && policy.Phases.Cold != nil {
+			// update
+			phases.PhasesCaster().Cold = policy.Phases.Cold
+		}
 	}
 
 	if cfg.HaveFrozen() {
 		froze := types.Phase{}
 		var actions types.IlmActionsVariant = esdsl.NewIlmActions()
 
+		if policy != nil {
+			// update
+			actions = policy.Phases.Frozen.Actions
+		}
+
 		if cfg.FrozenMinAge != "" {
 			froze.MinAge = cfg.FrozenMinAge
 		}
@@ -321,6 +478,11 @@ func IlmCreate(conf *cfg.Config, policyname string) error {
 
 		froze.Actions = actions.IlmActionsCaster()
 		phases.PhasesCaster().Frozen = &froze
+	} else {
+		if policy != nil && policy.Phases.Frozen != nil {
+			// update
+			phases.PhasesCaster().Frozen = policy.Phases.Frozen
+		}
 	}
 
 	if cfg.HaveDelete() {
@@ -328,6 +490,11 @@ func IlmCreate(conf *cfg.Config, policyname string) error {
 		delete := types.DeleteAction{}
 		var actions types.IlmActionsVariant = esdsl.NewIlmActions()
 
+		if policy != nil {
+			// update
+			actions = policy.Phases.Delete.Actions
+		}
+
 		if cfg.DeleteMinAge != "" {
 			del.MinAge = cfg.DeleteMinAge
 		}
@@ -339,16 +506,21 @@ func IlmCreate(conf *cfg.Config, policyname string) error {
 		actions.IlmActionsCaster().Delete = &delete
 		del.Actions = actions.IlmActionsCaster()
 		phases.PhasesCaster().Delete = &del
+	} else {
+		if policy != nil && policy.Phases.Delete != nil {
+			// update
+			phases.PhasesCaster().Delete = policy.Phases.Delete
+		}
 	}
 
 	put := &putlifecycle.Request{}
-	policy := &types.IlmPolicy{}
-	policy.IlmPolicyCaster().Phases = *phases.PhasesCaster()
-	put.Policy = policy
+	newpolicy := &types.IlmPolicy{}
+	newpolicy.IlmPolicyCaster().Phases = *phases.PhasesCaster()
+	put.Policy = newpolicy
 
 	ilm.Request(put)
 
-	_, err := ilm.Do(context.Background())
+	_, err = ilm.Do(context.Background())
 	if err != nil {
 		return fmt.Errorf("failed create ilm policy: %s", esErrorString(err))
 	}