---
title: Configuring Unleash
---

import Tabs from '@theme/Tabs'; import TabItem from '@theme/TabItem';

> This is the guide on how to configure **Unleash v5 self-hosted**.

## Must configure

### Database

In order for Unleash server to work, you need a running database and its connection details. See
the [database configuration section](#database-configuration) for the available options and configuration details.

## Nice to configure

### Unleash URL {#unleash-url}

- Configured with `UNLEASH_URL` ** Should be set to the public discoverable URL of your instance, so if your instance is
  accessed by your users at `https://unleash.mysite.com` use that. ** If you're deploying this to a subpath, include the
  subpath in this. So `https://mysite.com/unleash` will also be correct.
- Used to create
    - Reset password URLs
    - Welcome link for new users
    - Links in events for our Slack, Microsoft Teams and Datadog integrations

### Email server details {#email-server-details}

Used to send reset-password mails and welcome mails when onboarding new users. <br /> **NOTE** - If this is not
configured, you will not be able to allow your users to reset their own passwords.

For [more details, see here](./email-service.md)

### Minimum and recommended specifications

#### Minimum

| Resource | Request | Limit |
|----------|---------|-------|
| CPU      | 250m    | 500m  |
| Memory   | 200Mi   | 400Mi |

#### Recommended

| Resource | Request | Limit |
|----------|---------|-------|
| CPU      | 500m    | 1000m |
| Memory   | 512Mi   | 1Gi   |

## Further customization

In order to customize "anything" in Unleash you need to
use [Unleash from Node.js](./getting-started.md#option-two---from-nodejs) or start
the [docker image](./getting-started.md#option-one---use-docker) with environment variables.

```js
const unleash = require('unleash-server');

const unleashOptions = {
    db: {
        user: 'unleash_user',
        password: 'password',
        host: 'localhost',
        port: 5432,
        database: 'unleash',
        ssl: false,
        pool: {
            min: 0,
            max: 4,
            idleTimeoutMillis: 30000,
        },
    },
    enableRequestLogger: true,
};

unleash.start(unleashOptions);
```

**Available Unleash options include:**

- **authentication** - (object) - An object for configuring/implementing custom admin authentication

    - `enableApiToken` / `AUTH_ENABLE_API_TOKEN`:  `boolean` — Should unleash require API tokens for access? Defaults
      to `true`.
    - `type` / `AUTH_TYPE`: `string` — What kind of authentication to use. Possible values
        - `open-source` - Sign in with username and password. This is the default value.
        - `custom` - If implementing your own authentication hook, use this
        - `demo` - Only requires an email to sign in (was default in v3)
        - `none` - _Deprecated_ Turn off authentication completely. If no API token is provided towards /`api/client`
          or `/api/frontend` you will receive configuration for the "default" environment. We generally recommend you
          use the `demo` type for simple, insecure usage of Unleash. This auth type has many known limitations,
          particularly related to personalized capabilities such as favorites
          and [notifications](../../reference/notifications.md).
    - `customAuthHandler`: function `(app: any, config: IUnleashConfig): void` — custom express middleware handling
      authentication. Used when type is set to `custom`. Can not be set via environment variables.
    - `initialAdminUser`: `{ username: string, password: string} | undefined` — The initial admin username and password - Defaults to `admin` and `unleash4all`, respectively. Can be set using the `UNLEASH_DEFAULT_ADMIN_USERNAME` and `UNLEASH_DEFAULT_ADMIN_PASSWORD` environment variables.
    - `initApiTokens` / `INIT_ADMIN_API_TOKENS`, `INIT_CLIENT_API_TOKENS`,
          and `INIT_FRONTEND_API_TOKENS`: `ApiTokens[]` — Array of API tokens to create on startup. The tokens will only
          be created if the database doesn't already contain any API tokens. Example:

      ```ts
      [
        {
          environment: '*',
          project: '*',
          secret: '*:*.964a287e1b728cb5f4f3e0120df92cb5',
          type: ApiTokenType.ADMIN,
          username: 'some-user',
        },
      ];
      ```

      The tokens can be of any API token type. Note that _admin_ tokens **must** target all environments and projects (
      i.e. use `'*'` for `environments` and `project` and start the secret with `*:*.`).

      You can also use the environment variables `INIT_ADMIN_API_TOKENS`, `INIT_CLIENT_API_TOKENS`,
      and `INIT_FRONTEND_API_TOKENS`. All variables require a comma-separated list of API tokens to initialize (for
      instance `*:*.some-random-string, *:*.some-other-token`). The tokens found
      in `INIT_ADMIN_API_TOKENS`, `INIT_CLIENT_API_TOKENS`, and `INIT_FRONTEND_API_TOKENS` will be created as admin,
      client, and frontend tokens respectively, and Unleash will assign usernames automatically.

    -  `demoAllowAdminLogin` / `AUTH_DEMO_ALLOW_ADMIN_LOGIN`: `boolean` — Allows you to log in as the admin user when running Unleash with the `demo` auth type. To log in as the admin user, use `admin` as your email. Defaults to `false`.

- **databaseUrl** - (_deprecated_) the postgres database url to connect to. Only used if _db_ object is not specified,
  and overrides the _db_ object and any environment variables that change parts of it (like `DATABASE_SSL`). Should
  include username/password. This value may also be set via the `DATABASE_URL` environment variable. Alternatively, if
  you would like to read the database url from a file, you may set the `DATABASE_URL_FILE` environment variable with the
  full file path. The contents of the file must be the database url exactly.
- **db** - The database configuration object. See [the database configuration section](#database-configuration) for a
  full overview of the available properties.
- **disableLegacyFeaturesApi** (boolean) - whether to disable
  the [legacy features API](/reference/api/legacy/unleash/admin/features.md). Defaults
  to `false` (`DISABLE_LEGACY_FEATURES_API`). Introduced in Unleash 4.6.
- **email** - the email object configuring an SMTP server for sending welcome mails and password reset mails
    - `host` - The server URL to your SMTP server
    - `port` - Which port the SMTP server is running on. Defaults to 465 (Secure SMTP)
    - `secure` (boolean) - Whether to use SMTPS or not.
    - `sender` - Which email should be set as sender of mails being sent from Unleash?
    - `smtpuser` - Username for your SMTP server
    - `smtppass` - Password for your SMTP server
- ~~eventHook~~ (`function(event, data)`) - (_deprecated in Unleash 4.3_ in favor of
  the [Webhook integration](/reference/integrations/webhook.md). **Removed in Unleash 5**) If provided, this function
  will be invoked whenever a feature is mutated. The possible values for `event`
  are `'feature-created'`, `'feature-archived'` and `'feature-revived'`. The `data` argument contains information about
  the mutation. Its fields are `type` (string) - the event type (same as `event`); `createdBy` (string) - the user who
  performed the mutation; `data` - the contents of the change. The contents in `data` differs based on the event type;
  For `'feature-archived'` and `'feature-revived'`, the only field will be `name` - the name of the feature.
  For `'feature-created'` the data follows a schema defined in the
  code [here](https://github.com/Unleash/unleash/blob/7b7f0b84e8cddd5880dcf29c231672113224b9a7/src/lib/schema/feature-schema.ts#L77).
  See an [api here](/reference/api/legacy/unleash/admin/events).
- **getLogger** (function) - Used to register a [custom log provider](#how-do-i-configure-the-log-output).
- **logLevel** (`debug` | `info` | `warn` | `error` | `fatal`) - The lowest level to log at, also configurable using
  environment variable `LOG_LEVEL`.
- **enableRequestLogger** (boolean) - use this to enable logging for requested urls and response codes (default: false).
- **preHook** (function) - this is a hook if you need to provide any middlewares to express before `unleash` adds any.
  Express app instance is injected as first argument.
- **preRouterHook** (function) - use this to register custom express middlewares before the `unleash` specific routers
  are added.
- **secureHeaders** (boolean) - use this to enable security headers (HSTS, CSP, etc) when serving Unleash from HTTPS.
  Can also be configured through the environment variable `SECURE_HEADERS`.
- **additionalCspAllowedDomains** (CspAllowedDomains) - use this when you want to enable security headers but have
  additional domains you need to allow traffic to. You can set the following environment variables:
    - `CSP_ALLOWED_DEFAULT` to allow new defaultSrc (comma separated list)
    - `CSP_ALLOWED_FONT` to allow new fontSrc (comma separated list)
    - `CSP_ALLOWED_STYLE` to allow new styleSrc (comma separated list)
    - `CSP_ALLOWED_SCRIPT` to allow new scriptSrc (comma separated list)
    - `CSP_ALLOWED_IMG` to allow new imgSrc (comma separated list)
    - `CSP_ALLOWED_CONNECT` to allow new connectSrc (comma separated list)
    - `CSP_ALLOWED_FRAME` to allow new frameSrc (comma separated listed)
    - `CSP_ALLOWED_MEDIA` to allow new mediaSrc (comma separated list)
    - `CSP_ALLOWED_OBJECT` to allow new objectSrc (comma separated list)
- **server** - The server config object taking the following properties
    - _port_ - which port the unleash-server should bind to. If port is omitted or is 0, the operating system will
      assign an arbitrary unused port. Will be ignored if pipe is specified. This value may also be set via
      the `HTTP_PORT` environment variable
    - _host_ - which host the unleash-server should bind to. If host is omitted, the server will accept connections on
      the unspecified IPv6 address (::) when IPv6 is available, or the unspecified IPv4 address (0.0.0.0) otherwise.
      This value may also be set via the `HTTP_HOST` environment variable
    - _pipe_ - parameter to identify IPC endpoints.
      See https://nodejs.org/api/net.html#net_identifying_paths_for_ipc_connections for more details
    - _serverMetrics_ (boolean) - use this option to turn on/off prometheus metrics.
    - _baseUriPath_ (string) - use to register a base path for all routes on the application. For
      example `/my/unleash/base` (note the starting /). Defaults to `/`. Can also be configured through the environment
      variable `BASE_URI_PATH`.
    - _unleashUrl_ (string) - Used to specify the official URL this instance of Unleash can be accessed at for an end
      user. Can also be configured through the environment variable `UNLEASH_URL`.
    - _gracefulShutdownEnable_: (boolean) - Used to control if Unleash should shutdown gracefully (close connections,
      stop tasks,). Defaults to true. `GRACEFUL_SHUTDOWN_ENABLE`
    - _gracefulShutdownTimeout_: (number) - Used to control the timeout, in milliseconds, for shutdown Unleash
      gracefully. Will kill all connections regardless if this timeout is exceeded. Defaults to
      1000ms `GRACEFUL_SHUTDOWN_TIMEOUT`
    - _enableScheduledCreatedByMigration_: (boolean) - Schedules migrations that fills the field created_by_user_id for
      past events and features. It does it gradually in chunks and runs every 15 minutes so it doesn't affect the
      application's performance. Defaults to false. **NOTE:** If your installation started with Unleash v5.8 or later,
      you should not need this flag! `ENABLE_SCHEDULED_CREATED_BY_MIGRATION`
- **session** - The session config object takes the following options:
    - _ttlHours_ (number) - The number of hours a user session is allowed to live before a new sign-in is required.
      Defaults to 48 hours. `SESSION_TTL_HOURS`
    - _clearSiteDataOnLogout_ (boolean) - When `true`, a logout action will return a Clear Site Data response header
      instructing the browser to clear all cookies on the same domain Unleash is running on. If disabled unleash will
      only destroy and clear the session cookie. Defaults to _true_. `SESSION_CLEAR_SITE_DATA_ON_LOGOUT`
    - _cookieName_ - Name of the cookies used to hold the session id. Defaults to 'unleash-session'.
- **ui** (object) - Set of UI specific overrides. You may set the following keys: `environment`, `slogan`.
- **versionCheck** - the object deciding where to check for latest version
    - `url` - The url to check version (Defaults to `https://version.unleash.run`) - Overridable
      with (`UNLEASH_VERSION_URL`)
    - `enable` - Whether version checking is enabled (defaults to true) - Overridable with (`CHECK_VERSION`) (if
      anything other than `true`, does not check)
- **environmentEnableOverrides** - A list of environment names to force enable at startup. This is feature should be
  used with caution. When passed a list, this will enable each environment in that list and disable all other
  environments. You can't use this to disable all environments, passing an empty list will do nothing. If one of the
  given environments is not already enabled on startup then it will also enable projects and toggles for that
  environment. Note that if one of the passed environments doesn't already exist this will do nothing aside from log a
  warning.
- **clientFeatureCaching** - configuring memoization of the /api/client/features endpoint
    - `enabled` - set to true by default - Overridable with (`CLIENT_FEATURE_CACHING_ENABLED`)
    - `maxAge` - the time to cache features, set to 600 milliseconds by default - Overridable
      with (`CLIENT_FEATURE_CACHING_MAXAGE`) ) (accepts milliseconds)
- **frontendApi** - Configuration options for the [Unleash front-end API](/reference/front-end-api.md).
    - `refreshIntervalInMs` - how often (in milliseconds) front-end clients should refresh their data from the cache.
      Overridable with the `FRONTEND_API_REFRESH_INTERVAL_MS` environment variable.
- **accessControlMaxAge** - You can configure the max-age of the Access-Control-Max-Age header. Defaults to 86400
  seconds. Overridable with the `ACCESS_CONTROL_MAX_AGE` environment variable.
- **responseTimeWithAppNameKillSwitch** - use this to disable metrics with app names. This is enabled by default but may
  increase the cardinality of metrics causing Unleash memory usage to grow if your app name is randomly generated (which
  is not recommended). Overridable with the `UNLEASH_RESPONSE_TIME_WITH_APP_NAME_KILL_SWITCH` environment variable.
- **disableCompression** - Disables Express compression middleware, useful when configuring the application in a
  serverless environment. Defaults to `false`. Overridable with the `SERVER_DISABLE_COMPRESSION` environment variable.
- **keepAliveTimeout** - Use this to tweak connection keepalive timeout in seconds. Useful for hosted situations where
  you need to make sure your connections are closed before terminating the instance. Defaults to `15`. Overridable with
  the `SERVER_KEEPALIVE_TIMEOUT` environment variable.
  You can also set the environment variable `ENABLED_ENVIRONMENTS` to a comma delimited string of environment names to
  override environments.
- **metricsRateLimiting** - Use the following to tweak the rate limits
  for `/api/client/register`, `/api/client/metrics`, `/api/frontend/register` and `/api/frontend/metrics` POST endpoints
    - `clientMetricsMaxPerMinute` - How many requests per minute per IP is allowed against POST `/api/client/metrics`
      before returning 429. Set to 6000 by default (100rps) - Overridable with `REGISTER_CLIENT_RATE_LIMIT_PER_MINUTE`
      environment variable
    - `clientRegisterMaxPerMinute` - How many requests per minute per IP is allowed against POST `/api/client/register`
      before returning 429. Set to 6000 by default (100rps) - Overridable with `CLIENT_METRICS_RATE_LIMIT_PER_MINUTE`
      environment variable
    - `frontendMetricsMaxPerMinute` - How many requests per minute per IP is allowed against
      POST `/api/frontend/metrics` before returning 429. Set to 6000 by default (100rps) - Overridable
      with `FRONTEND_METRICS_RATE_LIMIT_PER_MINUTE` environment variable
    - `frontendRegisterMaxPerMinute` - How many requests per minute per IP is allowed against
      POST `/api/frontend/register` before returning 429. Set to 6000 by default (100rps) - Overridable
      with `REGISTER_FRONTEND_RATE_LIMIT_PER_MINUTE` environment variable
- **rateLimiting** - Use the following to tweak the rate limits for `POST /auth/simple` (Password-based login)
  and `POST /api/admin/user-admin` (Creating users)
    - `simpleLoginMaxPerMinute` - How many requests per minute per IP is allowed against POST `/auth/simple` before
      returning 429. Set to 10 by default - Overridable with `SIMPLE_LOGIN_LIMIT_PER_MINUTE` environment variable
    - `createUserMaxPerMinute` - How many requests per minute per IP is allowed against POST `/api/admin/user-admin`
      before returning 429. Set to 20 by default - Overridable with `CREATE_USER_RATE_LIMIT_PER_MINUTE` environment
      variable

### Disabling Auto-Start {#disabling-auto-start}

If you're using Unleash as part of a larger express app, you can disable the automatic server start by
calling `server.create`. It takes the same options as `server.start`, but will not begin listening for connections.

```js
const express = require('express');
const unleash = require('unleash-server');
const app = express();

const start = async () => {
    const instance = await unleash.create({
        databaseUrl: 'postgres://unleash_user:password@localhost:5432/unleash',
    });
    app.use(instance.app);
    console.log(`Unleash app generated and attached to parent application`);
};

start();
```

### Graceful shutdown {#shutdown-unleash}

> PS! Unleash will listen for the `SIGINT` signal and automatically trigger graceful shutdown of Unleash.

If you need to stop Unleash (close database connections, and stop running Unleash tasks) you may use the stop function.
Be aware that it is not possible to restart the Unleash instance after stopping it, but you can create a new instance of
Unleash.

```js
const express = require('express');
const unleash = require('unleash-server');
const app = express();

const start = async () => {
    const instance = await unleash.start({
        databaseUrl: 'postgres://unleash_user:password@localhost:5432/unleash',
        port: 4242,
    });

    //Sometime later
    await instance.stop();
    console.log('Unleash has now stopped');
};

start();
```

### Segment limits {#segments}

:::caution

Changing segment limits could have a negative impact on the performance of Unleash SDKs and cause network congestion.
Think twice before changing these values.

:::

Some facets of the [segments feature](/reference/segments.mdx) can be customized via environment variables. This lets
you change the [segment limits](/reference/segments.mdx#segment-limits) that Unleash uses.

`UNLEASH_STRATEGY_SEGMENTS_LIMIT` controls the maximum number of segments that can be applied to a single strategy. The
default is 5.

`UNLEASH_SEGMENT_VALUES_LIMIT` controls the maximum number of values that you can assign across a segment's constraints.
The default is 1000 (Since v5.1.0; it was 100 before v5.1.0)

## Securing Unleash {#securing-unleash}

You can integrate Unleash with your authentication provider (OAuth 2.0). Read more
about [securing unleash](./securing-unleash.md).

## How do I configure the log output? {#how-do-i-configure-the-log-output}

By default, `unleash` uses [log4js](https://github.com/nomiddlename/log4js-node) to log important information. It is
possible to swap out the logger provider (only when using Unleash programmatically). You do this by providing an
implementation of the **getLogger** function as This enables filtering of log levels and easy redirection of output
streams.

```javascript
function getLogger(name) {
    // do something with the name
    return {
        debug: console.log,
        info: console.log,
        warn: console.log,
        error: console.error,
    };
}
```

The logger interface with its `debug`, `info`, `warn` and `error` methods expects format string support as seen
in `debug` or the JavaScript `console` object. Many commonly used logging implementations cover this API, e.g., bunyan,
pino or winston.

## Database configuration

:::info

In-code configuration values take precedence over environment values: If you provide a database username both via
environment variables and in code with the Unleash options object, Unleash will use the in-code username.

:::

You cannot run the Unleash server without a database. You must provide Unleash with database connection details for it
to start correctly.

The available options are listed in the table below. Options can be specified either via JavaScript (only when starting
Unleash via code) or via environment variables. The "property name" column below gives the name of the property on the
Unleash options' `db` object.

| Property name            | Environment variable               | Default value                                    | Description                                                                                                                                                                    |
|--------------------------|------------------------------------|--------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `user`                   | `DATABASE_USERNAME`                | `unleash_user`                                   | The database username.                                                                                                                                                         |
| `password`               | `DATABASE_PASSWORD`                | `password`                                       | The database password.                                                                                                                                                         |
| `host`                   | `DATABASE_HOST`                    | `localhost`                                      | The database hostname.                                                                                                                                                         |
| `port`                   | `DATABASE_PORT`                    | `5432`                                           | The database port.                                                                                                                                                             |
| `database`               | `DATABASE_NAME`                    | `unleash`                                        | The name of the database.                                                                                                                                                      |
| `ssl`                    | `DATABASE_SSL`                     | N/A                                              | An object describing SSL options. In code, provide a regular JavaScript object. When using the environment variable, provide a **stringified JSON object**.                    |
|                          | `DATABASE_SSL_CA_CONFIG`           | N/A                                              | JSON file representing the SSL options, needs 4 keys set, `rejectUnauthorized`, `ca`, `cert`, `key`. the `ca`, `cert` and `key` keys needs to be ssl certificates as a string. |
|                          | `DATABASE_SSL_CA_FILE`             | N/A                                              | A path to a valid SSL CA file in `pem` format. Sets the `ca` key of the ssl object. See [https://node-postgres.com/features/ssl](pg docs)                                      |
|                          | `DATABASE_SSL_CERT_FILE`           | N/A                                              | A path to a valid SSL Cert file in `pem` format. Sets the `cert` key of the ssl object. See [https://node-postgres.com/features/ssl](pg docs)                                  |
|                          | `DATABASE_SSL_KEY_FILE`            | N/A                                              | A path to a valid SSL key file in `pem` format. Sets the `key` key of the ssl object. See [https://node-postgres.com/features/ssl](pg docs)                                    |
|                          | `DATABASE_SSL_REJECT_UNAUTHORIZED` | true if CA, CERT and KEY is set, false otherwise | If you use SSL connections to postgres, don't set this to false. It will turn off the security check of SSL. See [https://node-postgres.com/features/ssl](pg docs)             |
| `pool`                   | N/A (use the below variables)      |                                                  | An object describing database pool options. With environment variables, use the options below directly.                                                                        |
| `pool.min`               | `DATABASE_POOL_MIN`                | 0                                                | The minimum number of connections in the connection pool.                                                                                                                      |
| `pool.max`               | `DATABASE_POOL_MAX`                | 4                                                | The maximum number of connections in the connection pool.                                                                                                                      |
| `pool.idleTimeoutMillis` | `DATABASE_POOL_IDLE_TIMEOUT_MS`    | 30000                                            | The amount of time (in milliseconds) that a connection must be idle for before it is marked as a candidate for eviction.                                                       |
| `applicationName`        | `DATABASE_APPLICATION_NAME`        | `unleash`                                        | The name of the application that created this Client instance.                                                                                                                 |
| `schema`                 | `DATABASE_SCHEMA`                  | `public`                                         | The schema to use in the database.                                                                                                                                             |

Alternatively, you can use a
single-host [libpq connection string](https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING) to
connect to the database. You can provide it directly or from a file by using one of the below options. In JavaScript,
these are top-level properties of the root configuration object, _not_ the `db` object.

| Property name     | Environment variable | Default value | Description                                                                                                                                                                                                                                           |
|-------------------|----------------------|---------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `databaseUrl`     | `DATABASE_URL`       | N/A           | A string that matches a single-host [libpq connection string](https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING), such as `postgres://USER:PASSWORD@HOST:PORT/DATABASE`. Unleash does **not** support using multiple hosts. |
| `databaseUrlFile` | `DATABASE_URL_FILE`  | N/A           | The path to a file that contains a [libpq connection string](https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING).                                                                                                            |

Below is an example JavaScript configuration object.

```js
const unleashOptions = {
    databaseUrl: 'postgres:/USER:PASSWORD@HOST:PORT/DATABASE',
    databaseUrlFile: '/path/to/file',
    db: {
        user: 'unleash_user',
        password: 'password',
        host: 'localhost',
        port: 5432,
        database: 'unleash',
        ssl: false,
        pool: {
            min: 0,
            max: 4,
            idleTimeoutMillis: 30000,
        },
    },
};
```

### `db.ssl` vs `DATABASE_SSL` options

When initializing Unleash from code, you'll provide the `db.ssl` option as a JavaScript object. As such, any functions
will get evaluated before the object is used for configuration. When using the `DATABASE_SSL` environment variable, you
must provide the value as a stringified JSON object. The object will get parsed before being used for configuration, but
no further evaluation will take place.

If you want to read content from a file, you should either initialize Unleash via JavaScript or manually interpolate the
required values into the environment variable:

<Tabs groupId="db-configuration-options">

<TabItem value="js" label="JavaScript" default>

```js title="Reading from the file system in JavaScript"
const unleashOptions = {
    db: {
        // other options omitted for brevity
        ssl: {
            ca: fs.readFileSync('/path/to/server-certificates/root.crt').toString(),
        },
    },
};
```

</TabItem>

<TabItem value="env" label="Environment variables (bash)">

```bash title="Reading from the file system with bash"
DATABASE_SSL="{ \"ca\": \"$(cat /path/to/server-certificates/root.crt)\" }"
```

</TabItem>

</Tabs>

### Enabling self-signed certificates

To use self-signed certificates, you should set the SSL property `rejectUnauthorized` to `false` and set the `ca`
property to the value of the certificate:

<Tabs groupId="db-configuration-options">

<TabItem value="js" label="JavaScript" default>

```js title="Enable self-signed certificates"
const unleashOptions = {
    db: {
        // other options omitted for brevity
        ssl: {
            rejectUnauthorized: false,
            ca: fs.readFileSync('/path/to/server-certificates/root.crt').toString(),
        },
    },
};
```

</TabItem>

<TabItem value="env" label="Environment variables (bash)">

```bash title="Enable self-signed certificates"
DATABASE_SSL="{ \"rejectUnauthorized\": false, \"ca\": \"$(cat /path/to/server-certificates/root.crt)\" }"
```

</TabItem>

</Tabs>

Visit [the node-postgres library's SSL section](https://node-postgres.com/features/ssl) for more information.

### Supported Postgres SSL modes

Unleash builds directly on the [node-postgres library](https://node-postgres.com/features/ssl), so we support all the
same SSL modes that they support. As of version 8 (released on February 25th
2020), [node-postgres no longer supports all sslmodes](https://node-postgres.com/announcements#2020-02-25). For this
reason, Unleash cannot support all of Postgres' SSL modes. Specifically, Unleash **does not support** `sslmode=prefer`.
Instead you must know whether you require an SSL connection ahead of time.

### Recommended PostgreSQL spec

For PostgreSQL we recommend running with at least 1 CPU and at least 1Gi of memory, as well as at least 5Gi of SSD storage. From the cloud providers, look at:

| Provider | Machine                        |
|----------|--------------------------------|
| AWS      | db.t4g.small (2CPU / 2GB mem)  |
| Azure    | B2s (2CPU / 4GB mem )          |
| GCP      | 2 CPU / 4GB mem                |

Unleash SAAS runs on db.t4g.small and we're happy with that.


### Troubleshooting: database pooling connection timeouts {#database-pooling-connection-timeouts}

- Check the default values of connection pool about idle session handling.

- If you have a network component which closes idle sessions on the TCP layer, make sure that the connection
  pool's `idleTimeoutMillis` setting is lower than the `timespan` setting. If it isn't, then the network component will
  close the connection.

### Troubleshooting: missing metrics from connected Edge instances

If you're on Unleash 5.9.0 or newer, you might encounter issues with metrics from connected Edge instances. There are
two solutions to this, the recommended way and the one that will work for 5.9.0 but probably not for later versions

#### Recommended

- Make sure you're using the latest Edge, at least v17.0.0
- Make sure you have at least one valid client token configured. Either using the `--token` flag on startup, or via
  connecting an SDK with a valid token

#### Works in 5.9.0

- If you absolutely cannot upgrade your Edge instances to v17.0.0 or newer you can start Unleash with the environmental
  flag `UNLEASH_EXPERIMENTAL_EDGE_BULK_METRICS` set to `true`
- This will re-enable an endpoint that was disabled in 5.9.0 to allow users that cannot upgrade Edge just now to stay on
  an old Edge version, but still get client metrics.

### Proxying requests from Unleash

You can configure proxy services that intercept all outgoing requests from Unleash. This lets you use the Microsoft
Teams or the Webhook integration for external services, even if the internet can only be reached via a proxy on your
machine or container (for example if restricted by a firewall or similiar).

As an example, here's how you could do it using the [node-global-proxy](https://www.npmjs.com/package/node-global-proxy)
package:

```
const proxy = require("node-global-proxy").default;

proxy.setConfig({
    http: "http://user:password@url:8080",      //proxy adress, replace values as needed
    //https: "https://user:password@url:1080",  //if a https proxy is needed
  });

proxy.start();      //this starts the proxy, after this call all requests will be proxied
```

Using above code-snippet, every outgoing request from unleash or its integrations will be subsequently routed through
set proxy. If the proxy routing needs to be bypassed or stopped, its possible to stop it by using

`proxy.stop();`
