open-nomad/website/content/docs/concepts/workload-identity.mdx

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---
layout: docs
page_title: Workload Identity
description: Learn about Nomad's workload identity feature
---
# Workload Identity
Every workload running in Nomad is given an identity. When an [allocation][] is
accepted by the [plan applier][], the leader generates a Workload Identity for
each task in the allocation. This workload identity is a [JSON Web Token
(JWT)][] that has been signed by the leader's keyring. The workload identity
includes the following identity claims:
```json
{
"nomad_namespace": "default",
"nomad_job_id": "example",
"nomad_allocation_id": "5c6328f7-48c5-4d03-bada-91ef2e904d0d",
"nomad_task": "web"
}
```
# Using Workload Identity
While Nomad always creates and uses workload identities internally, the JWT is
not exposed to tasks by default.
To expose Workload Identity to tasks, add an [`identity`][identity-block] block
to your jobspec:
```hcl
task "example" {
identity {
# Expose Workload Identity in NOMAD_TOKEN env var
env = true
# Expose Workload Identity in ${NOMAD_SECRETS_DIR}/nomad_token file
file = true
}
}
```
# Workload Associated ACL Policies
You can associate additional ACL policies with workload identities by passing
the `-job`, `-group`, and `-task` flags to `nomad acl policy apply`. When Nomad
resolves a workload identity claim, it will automatically include policies that
match. If no matching policies exist, the workload identity does not have any
additional capabilities.
For example, to allow a workload access to secrets from the namespace "shared",
you can create the following policy file:
```hcl
namespace "shared" {
variables {
path "*" {
capabilities = ["read"]
}
}
}
```
You can then apply this policy to a specific task:
```shell-session
nomad acl policy apply \
-namespace default -job example -group cache -task redis \
redis-policy ./policy.hcl
```
You can also apply this policy to all tasks in the group by omitting the `-task`
flag:
```shell-session
nomad acl policy apply \
-namespace default -job example -group cache \
redis-policy ./policy.hcl
```
And you can apply this policy to all groups in the job by omitting both the
`-group` and `-task` flag:
```shell-session
nomad acl policy apply \
-namespace default -job example \
redis-policy ./policy.hcl
```
[allocation]: /nomad/docs/concepts/architecture#allocation
[identity-block]: /nomad/docs/job-specification/identity
[plan applier]: /nomad/docs/concepts/scheduling/scheduling
[JSON Web Token (JWT)]: https://datatracker.ietf.org/doc/html/rfc7519