---
layout: api
page_title: 'Identity Secret Backend: Entity Alias - HTTP API'
description: >-
  This is the API documentation for managing entity aliases in the identity
  store.
---

~> **NOTE:** Be careful in granting permissions to non-readonly identity endpoints.
If a user can modify an entity, they can grant it additional privileges through
policies.  If a user can modify an alias they can login with, they can bind it to
an entity with higher privileges.

## Create an Entity Alias

~> **IMPORTANT NOTE:** Prior to creating any alias it is important to consider the cardinality of the alias' name,
since there are potential security issues to be aware of. The main one revolves around alias reuse. It is possible
for multiple authenticated entities to be bound to the same alias, and therefore gain access to all of its privileges.
It is recommended, whenever possible, to create a unique alias for each entity. This is especially true in the case
of machine generated entities.

This endpoint creates a new alias for an entity.

| Method | Path                     |
| :----- | :----------------------- |
| `POST` | `/identity/entity-alias` |

### Parameters

- `name` `(string: <required>)` - Name of the alias. Name should be the identifier
  of the client in the authentication source. For example, if the alias belongs
  to userpass backend, the name should be a valid username within userpass
  auth method. If the alias belongs to GitHub, it should be the GitHub username. If the alias 
  belongs to an approle auth method, the name should be a valid RoleID.

- `id` `(string: <optional>)` - ID of the entity alias. If set, updates the
  corresponding entity alias.

- `canonical_id` `(string: <required>)` - Entity ID to which this alias belongs to.

- `mount_accessor` `(string: <required>)` - Accessor of the mount to which the
  alias should belong to.

- `custom_metadata` `(map<string|string>: <optional>)` - A map of arbitrary string to string valued 
  user-provided metadata meant to describe the alias.

### Sample Payload

```json
{
  "name": "testuser",
  "canonical_id": "404e57bc-a0b1-a80f-0a73-b6e92e8a52d3",
  "mount_accessor": "auth_userpass_e50b1a44",
  "custom_metadata": {
    "contact_email": "james_updated@example.com"
  }
}
```

### Sample Request

```shell-session
$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data @payload.json \
    http://127.0.0.1:8200/v1/identity/entity-alias
```

### Sample Response

```json
{
  "data": {
    "canonical_id": "404e57bc-a0b1-a80f-0a73-b6e92e8a52d3",
    "id": "34982d3d-e3ce-5d8b-6e5f-b9bb34246c31"
  }
}
```

## Read Entity Alias by ID

This endpoint queries the entity alias by its identifier.

| Method | Path                            |
| :----- | :------------------------------ |
| `GET`  | `/identity/entity-alias/id/:id` |

### Parameters

- `id` `(string: <required>)` – Identifier of entity alias.

### Sample Request

```shell-session
$ curl \
    --header "X-Vault-Token: ..." \
    http://127.0.0.1:8200/v1/identity/entity-alias/id/34982d3d-e3ce-5d8b-6e5f-b9bb34246c31
```

### Sample Response

```json
{
  "data": {
    "creation_time": "2017-07-25T21:41:09.820717636Z",
    "canonical_id": "404e57bc-a0b1-a80f-0a73-b6e92e8a52d3",
    "custom_metadata": {
      "contact_email":"james@example.com"
    },
    "id": "34982d3d-e3ce-5d8b-6e5f-b9bb34246c31",
    "last_update_time": "2017-07-25T21:41:09.820717636Z",
    "local": false,
    "metadata": {
      "group": "san_francisco",
      "region": "west"
    },
    "mount_accessor": "auth_userpass_e50b1a44",
    "mount_path": "userpass/",
    "mount_type": "userpass",
    "name": "testuser"
  }
}
```

## Update Entity Alias by ID

This endpoint is used to update an existing entity alias.

| Method | Path                            |
| :----- | :------------------------------ |
| `POST` | `/identity/entity-alias/id/:id` |

### Parameters

- `id` `(string: <required>)` – Identifier of the entity alias.

- `name` `(string: "")` - Name of the alias. Name should be the identifier
  of the client in the authentication source. For example, if the alias belongs
  to userpass backend, the name should be a valid username within userpass
  backend. If alias belongs to GitHub, it should be the GitHub username.

- `canonical_id` `(string: "")` - Entity ID to which this alias belongs to.

- `mount_accessor` `(string: "")` - Accessor of the mount to which the
  alias should belong to.

- `custom_metadata` `(map<string|string>: <optional>)` - A map of arbitrary string to string valued 
  user-provided metadata meant to describe the alias.

### Sample Payload

```json
{
  "name": "testuser",
  "canonical_id": "404e57bc-a0b1-a80f-0a73-b6e92e8a52d3",
  "mount_accessor": "auth_userpass_e50b1a44"
   "custom_metadata": {
    "contact_email": "james@example.com"
  }
}
```

### Sample Request

```shell-session
$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data @payload.json \
    http://127.0.0.1:8200/v1/identity/entity-alias/id/34982d3d-e3ce-5d8b-6e5f-b9bb34246c31
```

### Sample Response

```json
{
  "data": {
    "canonical_id": "404e57bc-a0b1-a80f-0a73-b6e92e8a52d3",
    "id": "34982d3d-e3ce-5d8b-6e5f-b9bb34246c31"
  }
}
```

## Delete Entity Alias by ID

This endpoint deletes an alias from its corresponding entity.

| Method   | Path                            |
| :------- | :------------------------------ |
| `DELETE` | `/identity/entity-alias/id/:id` |

### Parameters

- `id` `(string: <required>)` – Identifier of the entity alias.

### Sample Request

```shell-session
$ curl \
    --header "X-Vault-Token: ..." \
    --request DELETE \
    http://127.0.0.1:8200/v1/identity/entity-alias/id/34982d3d-e3ce-5d8b-6e5f-b9bb34246c31
```

## List Entity Aliases by ID

This endpoint returns a list of available entity aliases by their identifiers.

| Method | Path                                  |
| :----- | :------------------------------------ |
| `LIST` | `/identity/entity-alias/id`           |
| `GET`  | `/identity/entity-alias/id?list=true` |

### Sample Request

```shell-session
$ curl \
    --header "X-Vault-Token: ..." \
    --request LIST \
    http://127.0.0.1:8200/v1/identity/entity-alias/id
```

### Sample Response

```json
{
  "data": {
    "keys": [
      "2e8217fa-8cb6-8aec-9e22-3196d74ca2ba",
      "91ebe973-ec86-84db-3c7c-f760415326de",
      "92308b08-4139-3ec6-7af2-8e98166b4e0c",
      "a3b042e6-5cc1-d5a9-8874-d53a51954de2",
      "d5844921-017f-e496-2a9a-23d4a2f3e8a3"
    ]
  }
}
```
