Briefly, this error occurs when Elasticsearch fails to initialize a snapshot repository due to inconsistencies in the cluster state. This could be due to network issues, insufficient permissions, or a misconfigured repository. To resolve this issue, you can try the following: 1) Check and correct the repository configuration, 2) Ensure the Elasticsearch cluster has the necessary permissions to access the repository, 3) Check the network connectivity between the nodes, and 4) If the error persists, consider deleting and recreating the repository.
This guide will help you check for common problems that cause the log ” [{}] Exception when initializing repository generation in cluster state ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: repositories, blobstore, repository, cluster.
Overview
An Elasticsearch snapshot provides a backup mechanism that takes the current state and data in the cluster and saves it to a repository (read snapshot for more information). The backup process requires a repository to be created first. The repository needs to be registered using the _snapshot endpoint, and multiple repositories can be created per cluster. The following repository types are supported:
Repository types
| Repository type | Configuration type |
|---|---|
| Shared file system | Type: “fs” |
| S3 | Type : “s3” |
| HDFS | Type :“hdfs” |
| Azure | Type: “azure” |
| Google Cloud Storage | Type : “gcs” |
Examples
To register an “fs” repository:
PUT _snapshot/my_repo_01
{
"type": "fs",
"settings": {
"location": "/mnt/my_repo_dir"
}
}Notes and good things to know
- S3, HDFS, Azure and Google Cloud require a relevant plugin to be installed before it can be used for a snapshot.
- The setting, path.repo: /mnt/my_repo_dir needs to be added to elasticsearch.yml on all the nodes if you are planning to use the repo type of file system. Otherwise, it will fail.
- When using remote repositories, the network bandwidth and repository storage throughput should be high enough to complete the snapshot operations normally, otherwise you will end up with partial snapshots.
Log Context
Log “[{}] Exception when initializing repository generation in cluster state” classname is BlobStoreRepository.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
}
logger.trace("[{}] initializing repository generation in cluster state"; metadata.name());
repoDataInitialized = new ListenableActionFuture();
repoDataInitialized.addListener(listener);
final Consumer onFailure = e -> {
logger.warn(new ParameterizedMessage("[{}] Exception when initializing repository generation in cluster state";
metadata.name()); e);
final ActionListener existingListener;
synchronized (BlobStoreRepository.this) {
existingListener = repoDataInitialized;
repoDataInitialized = null;
