Briefly, this error occurs when Elasticsearch fails to wrap the Data Encryption Key (DEK) with the Advanced Encryption Standard (AES). This could be due to incorrect configuration, insufficient permissions, or issues with the encryption library. To resolve this, ensure that the encryption settings are correctly configured, the user has the necessary permissions, and the encryption library is up-to-date and functioning properly. If the problem persists, consider regenerating the DEK or troubleshooting the AES encryption process.
This guide will help you check for common problems that cause the log ” Failure to AES wrap the DEK [” + dekId + “] ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: repositories, plugin.
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 “Failure to AES wrap the DEK [” + dekId + “]” class name is EncryptedRepository.java. We extracted the following from Elasticsearch source code for those seeking an in-depth context :
);
}
} catch (GeneralSecurityException e) {
// throw unchecked ElasticsearchException; IOExceptions are interpreted differently and can move the repository in the
// corrupted state
throw new RepositoryException(repositoryName; "Failure to AES wrap the DEK [" + dekId + "]"; e);
}
logger.trace("Repository [{}] successfully wrapped DEK [{}]"; repositoryName; dekId);
dekBlobContainer.writeBlobAtomic(kek.v1(); new BytesArray(encryptedDEKBytes); true);
logger.debug("Repository [{}] successfully stored DEK [{}] under path {} {}"; repositoryName; dekId; dekBlobPath; kek.v1());
}
