Advanced Secrets Configuration

Vault implementations offer a variety of advanced configuration options. For specific configuration parameters for your vault backend, see the backend reference.

Query arguments

You can configure your vault backend with query arguments.

For example, the following query uses an option called prefix with the value SECURE_:

{vault://env/secret-config-value?prefix=SECURE_}

For more information on available configuration options, refer to respective vault backend documentation.

Environment variables

You can configure your vault backend with KONG_VAULT_<vault-backend>_<config_opt> environment variables.

For example, Kong Gateway might look for an environment variable that matches KONG_VAULT_ENV_PREFIX:

export KONG_VAULT_ENV_PREFIX=SECURE_

Vaults entity

You can configure your vault backend using the vaults entity.

The Vault entity can only be used once the database is initialized. Secrets for values that are used before the database is initialized can’t make use of the Vaults entity.

Create a Vault entity:

curl -i -X PUT http://HOSTNAME:8001/vaults/env-vault-1  \
  --data name=env \
  --data description='ENV vault for secrets' \
  --data config.prefix=SECRET_

Result:

{
    "config": {
        "prefix": "SECRET_"
    },
    "created_at": 1644929952,
    "description": "ENV vault for secrets",
    "id": "684ff5ea-7f65-4377-913b-880857f39251",
    "name": "env",
    "prefix": "env-vault-1",
    "tags": null,
    "updated_at": 1644929952
}

Config options depend on the associated backend used.

This lets you drop the configuration from environment variables and query arguments and use the entity name in the reference:

{vault://env-vault/secret-config-value}

Vaults CLI

Usage: kong vault COMMAND [OPTIONS]

Vault utilities for Kong Gateway.

Example usage:
 TEST=hello kong vault get env/test

The available commands are:
  get <reference>  Retrieves a value for <reference>

Options:
 -c,--conf    (optional string)  configuration file
 -p,--prefix  (optional string)  override prefix directory
 --v              verbose
 --vv             debug

Declarative configuration

Secrets management is supported in decK 1.16 and later.

You can configure a vault backend with decK. For example:

vaults:
- config:
    prefix: SECRET_
  description: ENV vault for secrets
  name: env
  prefix: env-vault

For more information on configuring vaults and using secret references in declarative configuration files, see Secret Management with decK.

Shared configuration parameters

Every vault supports the following configuration parameters:

Parameter	UI field name	Description
`vaults.description` optional	Description	An optional description for your vault.
`vaults.name`	N/A	The type of vault. Accepts one of: `env`, `gcp`, `aws`, or `hcv`.
`vaults.prefix`	Prefix	The reference prefix. You need this prefix to access secrets stored in this vault. For example, `{vault://env-vault/<some-secret>}`.

Most of the vaults also support secret rotation by using TTLs:

Parameter	Field name	Description
`vaults.config.ttl`	TTL	Time-to-live (in seconds) of a secret from the vault when it’s cached. The special value of 0 means “no rotation” and it’s the default. When using non-zero values, it is recommended that they’re at least 1 minute.
`vaults.config.neg_ttl`	Negative TTL	Time-to-live (in seconds) of a vault miss (no secret). Negatively cached secrets will remain valid until `neg_ttl` is reached. After this, Kong will attempt to refresh the secret again. The default value for `neg_ttl` is 0, which means no negative caching occurs.
`vaults.config.resurrect_ttl`	Resurrect TTL	Time (in seconds) for how long secrets will remain in use after they are expired (`config.ttl` is over). This is useful when a vault becomes unreachable, or when a secret is deleted from the Vault and isn’t replaced immediately. On this both cases, the Gateway will keep trying to refresh the secret for `resurrect_ttl` seconds. After that, it will stop trying to refresh. We recommend assigning a sufficiently high value to this configuration option to ensure a seamless transition in case there are unexpected issues with the Vault. The default value for `resurrect_ttl` is 1e8 seconds, which is about 3 years.