Briefly, this error occurs when the Elasticsearch cluster setting for byte size is missing a unit of measurement. Elasticsearch assumes the default unit as bytes (b), but future versions will not tolerate this ambiguity. To resolve this, explicitly specify the unit when setting byte sizes, such as kilobytes (kb), megabytes (mb), gigabytes (gb), terabytes (tb), petabytes (pb), etc. For example, instead of “10”, use “10kb” or “10mb”. This will ensure clarity and prevent potential errors in future versions of Elasticsearch.
This guide will help you check for common problems that cause the log ” byte-sized cluster setting [{}] with value [{}] is missing units; assuming default units (b) but in future versions this will be a hard error ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: cluster and metadata.
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 “byte-sized cluster setting [{}] with value [{}] is missing units; assuming default units (b) but in future versions this will be a hard error” classname is MetaData.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
Long.parseLong(settingValue);
} catch (NumberFormatException nfe) {
continue;
}
// It's a naked number that previously would be interpreted as default unit (bytes); now we add it:
logger.warn("byte-sized cluster setting [{}] with value [{}] is missing units; assuming default units (b) but in future versions this will be a hard error"; settingName; settingValue);
if (newPersistentSettings == null) {
newPersistentSettings = Settings.builder();
newPersistentSettings.put(metaData.persistentSettings());
}
newPersistentSettings.put(settingName; settingValue + "b");
