Volatile Configurations
Warning
This article describes working with YDB clusters using configuration V1. Configuration V1 was the main way to configure clusters managed by YDB versions below v25.1. Starting from version v25.1, YDB supports configuration V2, which is the recommended way to configure YDB clusters with version v25.1 and above. For clusters using configuration V2, the instructions in this article are not applicable.
If your cluster has already been updated to version v25.1 or above but still uses configuration V1, it is recommended to plan migration to configuration V2, as support for configuration V1 will be discontinued in future versions of YDB.
Volatile configurations are a special type of configurations that complement dynamic ones and are not persistent. That is, these configurations are reset when the Console tablet moves or restarts, as well as when the main configuration is updated.
Main usage scenarios:
- temporary configuration changes for debugging or testing;
- trial enabling of potentially dangerous settings. In case of cluster crash or restart, these settings will be automatically disabled.
These configurations are added to the end of the selector set, the description syntax is identical to selector syntax.
# Get all volatile configurations loaded on the cluster
ydb admin volatile-config fetch --all --output-directory <dir>
# Get volatile configuration with id=1
ydb admin volatile-config fetch --id 1
# Apply volatile configuration volatile.yaml to the cluster
ydb admin volatile-config add -f volatile.yaml
# Remove volatile configurations with id=1 and id=3 on the cluster
ydb admin volatile-config drop --id 1 --id 3
# Remove all volatile configurations on the cluster
ydb admin volatile-config drop --all
Example of Working with Volatile Configuration
Temporarily enabling blobstorage component logging settings to DEBUG on node host1.example.com:
# Request current metadata to form correct volatile configuration header
$ ydb admin config fetch --all
---
kind: MainConfig
cluster: "example-cluster-name"
version: 2
config:
# ...
---
kind: VolatileConfig
cluster: "example-cluster-name"
version: 2
id: 1
selector_config:
# ...
# Load configuration with version 2, cluster name example-cluster-name and identifier 2
$ ydb admin volatile-config add -f - <<<EOF
metadata:
kind: VolatileConfig
cluster: "example-cluster-name"
version: 2
id: 2
selector_config:
- description: Set blobstorage logging level to DEBUG
selector:
node_host: host1.example.com
config:
log_config: !inherit
entry: !inherit_key:component
- component: BLOBSTORAGE
level: 8
EOF
# ...
# log analysis
# ...
# Remove configuration
$ ydb admin volatile-config drop --id 2