---
layout: docs
page_title: acl Stanza - Agent Configuration
description: >-
  The "acl" stanza configures the Nomad agent to enable ACLs and tune various
  parameters.
---

# `acl` Stanza

<Placement groups={['acl']} />

The `acl` stanza configures the Nomad agent to enable ACLs and tunes various
ACL parameters. Learn more about configuring Nomad's ACL system in the [Secure
Nomad with Access Control guide][secure-guide].

```hcl
acl {
  enabled = true
  token_ttl = "30s"
  policy_ttl = "60s"
}
```

## `acl` Parameters

- `enabled` `(bool: false)` - Specifies if ACL enforcement is enabled. All other
  ACL configuration options depend on this value. Note that the Nomad command
  line client will send requests for client endpoints such as `alloc exec`
  directly to Nomad clients whenever they are accessible. In this scenario, the
  client will enforce ACLs, so both servers and clients should have ACLs enabled.

- `token_ttl` `(string: "30s")` - Specifies the maximum time-to-live (TTL) for
  cached ACL tokens. This does not affect servers, since they do not cache tokens.
  Setting this value lower reduces how stale a token can be, but increases
  the request load against servers. If a client cannot reach a server, for example
  because of an outage, the TTL will be ignored and the cached value used.

- `policy_ttl` `(string: "30s")` - Specifies the maximum time-to-live (TTL) for
  cached ACL policies. This does not affect servers, since they do not cache policies.
  Setting this value lower reduces how stale a policy can be, but increases
  the request load against servers. If a client cannot reach a server, for example
  because of an outage, the TTL will be ignored and the cached value used.

- `replication_token` `(string: "")` - Specifies the Secret ID of the ACL token
  to use for replicating policies and tokens. This is used by servers in non-authoritative
  region to mirror the policies and tokens into the local region from [authoritative_region][authoritative-region].

[secure-guide]: https://learn.hashicorp.com/collections/nomad/access-control
[authoritative-region]: /docs/configuration/server#authoritative_region
