# New nodes added to cluster are not rebalancing

**URL:** <https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715>\
**Category:** Elasticsearch\
**Created:** [November 18, 2024, 6:32pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715 "2024-11-18T18:32:52Z")\
**Posts on this page:** 10\
**Page:** 1

<div class="post-metadata">

**Author:** ![mpniel](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/mpniel/32/113170_2.png) [@mpniel](https://discuss.elastic.co/u/mpniel)\
**Post date:** [November 18, 2024, 6:32pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/1 "2024-11-18T18:32:52Z")

</div>

I have 50 nodes in the Elasticsearch 7.5 cluster and added five new nodes. All shards are balancing between nodes . These five new nodes for some reason do not go into balance, and their disks are near empty. There are some shards on them.  
‏There is no recover activity in the cluster .  
What could be the problem?

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<div class="post-metadata">

**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\
**Post date:** [November 18, 2024, 6:36pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/2 "2024-11-18T18:36:35Z")

</div>

What is the full output of the [cluster stats API](https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-stats.html)?

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<div class="post-metadata">

**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\
**Post date:** [November 18, 2024, 7:15pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/5 "2024-11-18T19:15:08Z")

</div>

I can not access it. Please post it here or upload it as a gist.

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<div class="post-metadata">

**Author:** ![mpniel](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/mpniel/32/113170_2.png) [@mpniel](https://discuss.elastic.co/u/mpniel)\
**Post date:** [November 18, 2024, 7:27pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/6 "2024-11-18T19:27:55Z")

</div>

```auto

{

  "_nodes" : {

    "total" : 54,

    "successful" : 54,

    "failed" : 0

  },

  "cluster_name" : "elsgen_cls",

  "cluster_uuid" : "nl-aqpHnSIuUYAplZlAjxQ",

  "timestamp" : 1731955879460,

  "status" : "green",

  "indices" : {

    "count" : 7286,

    "shards" : {

      "total" : 20678,

      "primaries" : 10339,

      "replication" : 1.0,

      "index" : {

        "shards" : {

          "min" : 2,

          "max" : 20,

          "avg" : 2.838045566840516

        },

        "primaries" : {

          "min" : 1,

          "max" : 10,

          "avg" : 1.419022783420258

        },

        "replication" : {

          "min" : 1.0,

          "max" : 1.0,

          "avg" : 1.0

        }

      }

    },

    "docs" : {

      "count" : 55789118611,

      "deleted" : 1074058799

    },

    "store" : {

      "size_in_bytes" : 131433338519174

    },

    "fielddata" : {

      "memory_size_in_bytes" : 32942497780,

      "evictions" : 0

    },

    "query_cache" : {

      "memory_size_in_bytes" : 139011644017,

      "total_count" : 37071265229,

      "hit_count" : 4708036564,

      "miss_count" : 32363228665,

      "cache_size" : 1623403,

      "cache_count" : 142226890,

      "evictions" : 140603487

    },

    "completion" : {

      "size_in_bytes" : 9804

    },

    "segments" : {

      "count" : 414197,

      "memory_in_bytes" : 82211562177,

      "terms_memory_in_bytes" : 23123875929,

      "stored_fields_memory_in_bytes" : 46169186608,

      "term_vectors_memory_in_bytes" : 0,

      "norms_memory_in_bytes" : 741823936,

      "points_memory_in_bytes" : 10210961612,

      "doc_values_memory_in_bytes" : 1965714092,

      "index_writer_memory_in_bytes" : 4537245308,

      "version_map_memory_in_bytes" : 34433767,

      "fixed_bit_set_memory_in_bytes" : 8691405256,

      "max_unsafe_auto_id_timestamp" : 1731954710286,

      "file_sizes" : { }

    }

  },

  "nodes" : {

   "count" : {

      "total" : 54,

      "coordinating_only" : 3,

      "data" : 48,

      "ingest" : 48,

      "master" : 3,

      "ml" : 0,

      "voting_only" : 0

    },

    "versions" : [

      "7.5.1"

    ],

    "os" : {

      "available_processors" : 444,

      "allocated_processors" : 444,

      "names" : [

        {

          "name" : "Linux",

          "count" : 54

        }

      ],

      "pretty_names" : [

        {

          "pretty_name" : "CentOS Linux 7 (Core)",

          "count" : 54

        }

      ],

      "mem" : {

        "total_in_bytes" : 2758616629248,

        "free_in_bytes" : 171232272384,

        "used_in_bytes" : 2587384356864,

        "free_percent" : 6,

        "used_percent" : 94

      }

    },

    "process" : {

      "cpu" : {

        "percent" : 251

      },

      "open_file_descriptors" : {

        "min" : 1575,

        "max" : 20321,

        "avg" : 9382

      }

    },

    "jvm" : {

      "max_uptime_in_millis" : 90227690742,

      "versions" : [

        {

          "version" : "13.0.1",

          "vm_name" : "OpenJDK 64-Bit Server VM",

          "vm_version" : "13.0.1+9",

          "vm_vendor" : "AdoptOpenJDK",

          "bundled_jdk" : true,

          "using_bundled_jdk" : true,

          "count" : 54

        }

      ],

      "mem" : {

        "heap_used_in_bytes" : 816650669464,

        "heap_max_in_bytes" : 1719563845632

      },

      "threads" : 9004

    },

    "fs" : {

      "total_in_bytes" : 210109265416192,

      "free_in_bytes" : 78639043887104,

      "available_in_bytes" : 78639043887104

    },

    "plugins" : [

      {

        "name" : "readonlyrest",

        "version" : "1.27.0",

        "elasticsearch_version" : "7

```

---

<div class="post-metadata">

**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\
**Post date:** [November 18, 2024, 7:43pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/7 "2024-11-18T19:43:42Z")

</div>

Is the hardware specification the same for all data nodes in the cluster? How many shards do the new nodes hold? Is data currently being relocated to the new notes?

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<div class="post-metadata">

**Author:** ![mpniel](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/mpniel/32/113170_2.png) [@mpniel](https://discuss.elastic.co/u/mpniel)\
**Post date:** [November 18, 2024, 8:56pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/8 "2024-11-18T20:56:49Z")

</div>

That is exactly the question. Without doing anything the nodes should balance on their own. That's how it was the previous times we added. There are currently only several shards on the new aded nodes.

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<div class="post-metadata">

**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\
**Post date:** [November 19, 2024, 5:44am UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/9 "2024-11-19T05:44:59Z")

</div>

> [@mpniel](#):
>
> I have 50 nodes in the Elasticsearch 7.5 cluster

You are running a very old version that has been EOL a very long time so I would recommend you upgrade to the latest version.

> [@Christian\_Dahlqvist](#):
>
> Is the hardware specification the same for all data nodes in the cluster?

Is the hardware specification exactly the same across the board?

Are there any [current recoveries in progress](https://www.elastic.co/guide/en/elasticsearch/reference/current/cat-recovery.html)? If so, do any of these involve the new nodes?

Is there anything in your master nodes log that indicates issues persisting or propagating the cluster state?

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<div class="post-metadata">

**Author:** ![mpniel](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/mpniel/32/113170_2.png) [@mpniel](https://discuss.elastic.co/u/mpniel)\
**Post date:** [November 19, 2024, 8:50am UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/10 "2024-11-19T08:50:18Z")

</div>

there are many unassigned shards.

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<div class="post-metadata">

**Author:** ![kdwolf](https://avatars.discourse-cdn.com/v4/letter/k/df788c/32.png) [@kdwolf](https://discuss.elastic.co/u/kdwolf)\
**Post date:** [November 21, 2024, 12:04pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/11 "2024-11-21T12:04:04Z")

</div>

What roles those new nodes have? If they have data role, which one(s): data\_content, hot etc. Are those roles exactly the same as on the other nodes?

@Christian_Dahlqvist is it sufficient to have only 3 master / 3 coordinating nodes for a total of 55 (as I understand there were 50 and now added 5 more)?

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<div class="post-metadata">

**Author:** ![Christian\_Dahlqvist](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/christian_dahlqvist/32/4617_2.png) [@Christian\_Dahlqvist](https://discuss.elastic.co/u/Christian_Dahlqvist)\
**Post date:** [November 21, 2024, 12:12pm UTC](https://discuss.elastic.co/t/new-nodes-added-to-cluster-are-not-rebalancing/370715/12 "2024-11-21T12:12:11Z")

</div>

3 dedicated master nodes is generally recommended for any large size cluster. Only one of them will act as master at any point in time and the others are only there for redundancy. Adding more dedicated therefore just add redundancy and does not affect performance.

It is important though that the master nodes have sufficient resources, which is why I asked to check the logs on the elected master node for any sign of issues.

Coordinating only nodes are not generally required at all but can for some use cases help.
