Kubecost's ETL is a computed cache based on Prometheus's metrics, from which the user can perform all possible Kubecost queries. The ETL data is stored in a PersistentVolume
mounted to the kubecost-cost-analyzer
pod.
There are a number of reasons why you may want to backup this ETL data:
- To ensure a copy of your Kubecost data exists, so that you can restore the data if needed
- To reduce the amount of historical data stored in Prometheus/Thanos, and instead retain historical ETL data
Note: Beginning in v1.100 this feature will be enabled by default if you have Thanos enabled. To opt out, set
.Values.kubecostModel.etlBucketConfigSecret=""
We provide cloud storage backups for ETL backing storage. Backups are not the typical approach of "halt all reads/writes and dump the database." Instead, the backup system is a transparent feature that will always ensure that local ETL data is backed up, and if local data is missing, it can be retrieved from backup storage. This feature protects users from accidental data loss by ensuring that previously backed up data can be restored at runtime.
Note: Durable backup storage functionality is only part of Kubecost Enterprise.
When the ETL pipeline collects data, it stores both daily and hourly (if configured) cost metrics on a configured storage. This defaults to a persistent volume based disk storage, but can be configured to use external durable storage on the following providers:
- AWS S3
- Azure Blob Storage
- Google Cloud Storage
This configuration secret follows the same layout documented for Thanos here.
You will need to create a file named object-store.yaml
using the chosen storage provider configuration (documented below), and run the following command to create the secret from this file:
kubectl create secret generic <YOUR_SECRET_NAME> -n kubecost --from-file=object-store.yaml
Note: The file must be named
object-store.yaml
If you have already configured Thanos following this documentation, you can reuse the previously created bucket configuration secret.
Setting .Values.kubecostModel.etlBucketConfigSecret=kubecost-thanos
will enable the backup feature. This will backup all ETL data to the same bucket being used by Thanos.
The configuration schema for S3 is documented here. For reference, here's an example:
type: S3
config:
bucket: "my-bucket"
endpoint: "s3.amazonaws.com"
region: "us-west-2"
access_key: "<AWS_ACCESS_KEY>"
secret_key: "<AWS_SECRET_KEY>"
insecure: false
signature_version2: false
put_user_metadata:
"X-Amz-Acl": "bucket-owner-full-control"
prefix: "" # Optional. Specify a path within the bucket (e.g. "kubecost/etlbackup").
The configuration schema for Google Cloud Storage is documented here. For reference, here's an example:
type: GCS
config:
bucket: "my-bucket"
service_account: |-
{
"type": "service_account",
"project_id": "project",
"private_key_id": "abcdefghijklmnopqrstuvwxyz12345678906666",
"private_key": "-----BEGIN PRIVATE KEY-----\...\n-----END PRIVATE KEY-----\n",
"client_email": "[email protected]",
"client_id": "123456789012345678901",
"auth_uri": "https://accounts.google.com/o/oauth2/auth",
"token_uri": "https://oauth2.googleapis.com/token",
"auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
"client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/kubecost%40gitpods.iam.gserviceaccount.com"
}
prefix: "" # Optional. Specify a path within the bucket (e.g. "kubecost/etlbackup").
The configuration schema for Azure is documented here. For reference, here's an example:
type: AZURE
config:
storage_account: "<STORAGE_ACCOUNT>"
storage_account_key: "<STORAGE_ACCOUNT_KEY>"
container: "my-bucket"
endpoint: ""
prefix: "" # Optional. Specify a path within the bucket (e.g. "kubecost/etlbackup").
Because Storj is S3 compatible, it can be be used as a drop-in replacement for S3. After an S3 Compatible Access Grant has been created, an example configuration would be:
type: S3
config:
bucket: "my-bucket"
endpoint: "gateway.storjshare.io"
access_key: "<STORJ_ACCESS_KEY>"
secret_key: "<STORJ_SECRET_KEY>"
insecure: false
signature_version2: false
http_config:
idle_conn_timeout: 90s
response_header_timeout: 2m
insecure_skip_verify: false
trace:
enable: true
part_size: 134217728
prefix: "" # Optional. Specify a path within the bucket (e.g. "kubecost/etlbackup").
If Kubecost was installed via Helm, ensure the following value is set.
kubecostModel:
etlBucketConfigSecret: <YOUR_SECRET_NAME>
If you are using an existing disk storage option for your ETL data, enabling the durable backup feature will retroactively back up all previously stored data*. This feature is also fully compatible with the existing S3 backup feature.
* If you are using a memory store for your ETL data with a local disk backup (kubecostModel.etlFileStoreEnabled: false
), the backup feature will simply replace the local backup. In order to take advantage of the retroactive backup feature, you will need to update to file store (kubecostModel.etlFileStoreEnabled: true
). This option is now enabled by default in the Helm chart.
The simplest way to backup Kubecost's ETL is to copy the pod's ETL store to your local disk. You can then send that file to any other storage system of your choice. We provide a script to do that.
To restore the backup, untar the results of the etl-backup script into the ETL directory pod.
kubectl cp -c cost-model <untarred-results-of-script> <kubecost-namespace>/<kubecost-pod-name>/var/configs/db/etl
There is also a Bash script available to restore the backup here.
Currently, this feature is still in development, but there is currently a status card available on the diagnostics page that will eventually show the status of the backup system:
In some scenarios like when using Memory store, setting kubecostModel.etlHourlyStoreDurationHours
to a value of 48
hours or less will cause ETL backup files to become truncated. The current recomendation is to keep etlHourlyStoreDurationHours at its default of 49
hours.