Allocation already exists – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 8-8.2

Briefly, this error occurs when Elasticsearch tries to allocate a shard to a node, but the shard is already allocated. This can happen due to a misconfiguration or a network partition. To resolve this issue, you can try the following: 1) Check the cluster health and ensure all nodes are connected. 2) Verify the shard allocation settings in your Elasticsearch configuration. 3) If the problem persists, you may need to manually reroute the shard using the cluster reroute API. Always ensure to backup your data before making any changes to your cluster.

This guide will help you check for common problems that cause the log ” [{}] allocation already exists ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: allocation, plugin.

Log Context

Log “[{}] allocation already exists” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 return modelRoutingEntries.containsKey(modelId);
 }  public Builder addNewAllocation(String modelId; TrainedModelAllocation.Builder allocation) {
 if (modelRoutingEntries.containsKey(modelId)) {
 throw new ResourceAlreadyExistsException("[{}] allocation already exists"; modelId);
 modelRoutingEntries.put(modelId; allocation);
 isChanged = true;
 return this;


How helpful was this guide?

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?