Manage KMS using the CLI

Explore commands for managing Key Management System (KMS) integration with the WEKA system using the CLI.

Using the CLI, you can:

Configure the KMS

Command: weka security kms set

To integrate the Key Management Service (KMS) with the WEKA system, use the provided command line for adding or updating the KMS configuration. Ensure that the KMS is preconfigured, and both the key and a valid token are readily available.

Run the following command to establish a connection between the WEKA system and the configured Vault KMS.

weka security kms set <type> <address> <key-identifier> [--token token] [--namespace namespace] [--client-cert client-cert] [--client-key client-key] [--ca-cert ca-cert]

Parameters

Example:

Setting the WEKA system with a Vault KMS:

weka security kms set vault https://vault-dns:8200 weka-key --token s.nRucA9Gtb3yNVmLUK221234

Setting the WEKA system with a KMIP complaint KMS (SmartKey example):

weka security kms set kmip amer.smartkey.io:5696 b2f81234-c0f6-4d63-b5b3-84a82e231234 --client-cert smartkey_cert.pem --client-key smartkey_key.pem

View the KMS configuration

Command: weka security kms

Use this command to show the details of the configured KMS.

Remove the KMS configuration

Command: weka security kms unset

Use this command to remove the KMS from the Weka system. It is only possible to remove a KMS configuration if no encrypted filesystems exist.

To force remove a KMS even if encrypted filesystems exist, use the --allow-downgrade attribute. In such cases, the encrypted filesystem keys are re-encrypted with local encryption and may be compromised.

Re-wrap filesystem keys

Command: weka security kms rewrap

If the KMS key is compromised or requires rotation, the KMS admin can rotate the key in the KMS. In such cases, this command is used to re-encrypt the encrypted filesystem keys with the new KMS master key.

weka security kms rewrap [--new-key-uid new-key-uid]

Parameters

WEKA does not automatically re-encrypt existing filesystem keys with the new KMS key for the existing snapshots already uploaded with the old encrypted keys.

In contrast to Vault KMS, the process of re-wrapping a KMIP-based KMS involves generating a new key within the KMS, rather than rotating the existing key. Therefore, it is essential to retain the old key within the KMS to ensure the ability to decrypt older Snap-to-Object snapshots.

Set up vault configuration

Enable 'Transit' secret engine in vault

The WEKA system uses encryption-as-a-service capabilities of the KMS to encrypt/decrypt the filesystem keys. This requires the configuration of Vault with the transit secret engine.

$ vault secrets enable transit
Success! Enabled the transit secrets engine at: transit/

Set up a master key for the WEKA system

Once the transit secret engine is set up, a master key for use with the WEKA system must be created.

$ vault write -f transit/keys/weka-key
Success! Data written to: transit/keys/weka-key

It is possible to either create a different key for each WEKA cluster or to share the key between different WEKA clusters.

Related information:

Vault transit secret-engine documentation

Create a policy for master key permissions

  • Create a weka_policy.hcl file with the following content:

path "transit/+/weka-key" {
  capabilities = ["read", "create", "update"]
}
path "transit/keys/weka-key" {
  capabilities = ["read"]
}

This limits the capabilities so there is no permission to destroy the key, using this policy. This protection is important when creating an API token.

  • Create the policy using the following command:

$ vault policy write weka weka_policy.hcl

Obtain an API token from the vault

Authentication from the WEKA system to Vault relies on an API token. Since the WEKA system must always be able to communicate with the KMS, a periodic service token must be used.

  • Verify that thetoken authentication method in Vault is enabled. This can be performed using the following command:

$ vault auth list

Path         Type        Description
----         ----        -----------
token/       token       token based credentials
  • To enable the token authentication method use the following command:

$ vault auth enable token
  • Log into the KMS system using any of the identity methods supported by Vault. The identity should have permission to use the previously-set master key.

  • Create a token role for the identity using the following command:

$ vault write auth/token/roles/weka allowed_policies="weka" period="768h"

The period is the time set for a renewal request. If no renewal is requested during this time period, the token will be revoked and a new token must be retrieved from Vault and set in the WEKA system.

  • Generate a token for the logged-in identity using the following command:

$ vault token create -role=weka

Key                  Value
---                  -----
token                s.nRucA9Gtb3yNVmLUK221234
token_accessor       4Nm9BvIVS4HWCgLATc3r1234
token_duration       768h
token_renewable      true
token_policies       ["default"]
identity_policies    []
policies             ["default"]

For more information on obtaining an API token, refer to Vault Tokens documentation.

The WEKA system does not automatically renew the API token lease. It can be renewed using the Vault CLI/API. It is also possible to define a higher maximum token value (max_lease_ttl)by changing the Vault Configuration file.

Obtain a certificate for a KMIP-based KMS

The method for obtaining a client certificate and key and set it via the KMS is different for each KMS. The certificate itself is generated using OpenSSL, with a UID obtained from the KMS.

Example:

openssl req -x509 -newkey rsa:4096 -keyout client-key.pem -out client-cert.pem -days 365 -nodes -subj '/CN=f283c99b-f173-4371-babc-572961161234'

See the specific KMS documentation to create a certificate and link it to the Weka cluster in the KMS with sufficient privileges (encrypt/decrypt).

For example, for SmartKey KMS, follow similar instructions as suggested here to create a client certificate and key, and assign a certificate for Weka within SmartKey.