Briefly, this error occurs when Elasticsearch is trying to refresh the UUIDs for repositories, which is a part of the snapshot and restore process. This could be due to a configuration issue, network problem, or a problem with the repository itself. To resolve this issue, you can check the repository configuration, ensure the network connectivity between Elasticsearch and the repository, and verify the health and status of the repository. If the problem persists, you may need to recreate the repository or restart the Elasticsearch cluster.
This guide will help you check for common problems that cause the log ” refreshing repository UUIDs for repositories [{}] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: repositories, repository.
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 “refreshing repository UUIDs for repositories [{}]” classname is RestoreService.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
logger.debug("repository UUID refresh is not required");
refreshListener.onResponse(null);
return;
}
logger.info("refreshing repository UUIDs for repositories [{}]";
repositories.stream().map(repository -> repository.getMetadata().name()).collect(Collectors.joining(";")));
final ActionListener groupListener = new GroupedActionListener(new ActionListener>() {
@Override
public void onResponse(Collection ignored) {
logger.debug("repository UUID refresh completed");
