--- title: acme_server (Caddyfile directive) --- # acme_server An embedded [ACME protocol](https://tools.ietf.org/html/rfc8555) server handler. This allows a Caddy instance to issue certificates for any other ACME-compatible software (including other Caddy instances). When enabled, requests matching the path `/acme/*` will be handled by the ACME server. ## Client configuration Using ACME server defaults, ACME clients should simply be configured to use `https://localhost/acme/local/directory` as their ACME endpoint. (`local` is the ID of Caddy's default CA.) ## Syntax ```caddy-d acme_server [] { ca } ``` - **ca** specifies the ID of the certificate authority with which to sign certificates. The default is `local`, which is Caddy's default CA, intended for locally-used, self-signed certificates, which is most common in dev environments. For broader use, it is recommended to specify a different CA to avoid confusion. If the CA with the given ID does not already exist, it will be created. See the [PKI app global options](/docs/caddyfile/options#pki-options) to configure alternate CAs.