Briefly, this error occurs when Elasticsearch is unable to delete the metadata associated with a snapshot, possibly due to insufficient permissions, a corrupted snapshot, or a network issue. To resolve this, you can try the following: 1) Check and adjust the permissions of the Elasticsearch user to ensure it has the necessary rights to delete metadata. 2) If the snapshot is corrupted, try to restore it or delete it completely. 3) If it’s a network issue, ensure that the connection between Elasticsearch and the snapshot repository is stable.
This guide will help you check for common problems that cause the log ” [{}] failed to remove snapshot metadata ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: metadata, snapshot.
Overview
Metadata in Elasticsearch refers to additional information stored for each document. This is achieved using the specific metadata fields available in Elasticsearch. The default behavior of some of these metadata fields can be customized during mapping creation.
Examples
Using _meta meta-field for storing application-specific information with the mapping:
PUT /my_index?pretty
{
"mappings": {
"_meta": {
"domain": "security",
"release_information": {
"date": "18-01-2020",
"version": "7.5"
}
}
}
}Notes
- In version 2.x, Elasticsearch had a total 13 meta fields available, which are: _index, _uid, _type, _id, _source, _size, _all, _field_names, _timestamp, _ttl, _parent, _routing, _meta
- In version 5.x, _timestamp and _ttl meta fields were removed.
- In version 6.x, the _parent meta field was removed.
- In version 7.x, _uid and _all meta fields were removed.
Log Context
Log “[{}] failed to remove snapshot metadata” classname is SnapshotsService.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
);
}
@Override
public void onFailure(Exception e) {
logger.warn(() -> new ParameterizedMessage("[{}] failed to remove snapshot metadata"; snapshot); e);
failSnapshotCompletionListeners(
snapshot;
new SnapshotException(snapshot; "Failed to remove snapshot from cluster state"; e)
);
failAllListenersOnMasterFailOver(e);
