Note that we can either give path to certificate file or directly the file content itself ([like in this TOML example](/user-guide/kv-config/#upload-the-configuration-in-the-key-value-store)).
Traefik will only try to generate a Let's encrypt certificate if the domain cannot be checked by the provided certificates.
### Cluster mode
#### Prerequisites
Before to use Let's Encrypt in a Traefik cluster, take a look to [the key-value store explanations](/user-guide/kv-config) and more precisely to [this section](/user-guide/kv-config/#store-configuration-in-key-value-store) in the way to know how to migrate from a acme local storage *(acme.json file)* to a key-value store configuration.
The `/ping` health-check URL is enabled together with the web admin panel, enabled with the command-line `--web` or config file option `[web]`.
Thus, if you have a regular path for `/foo` and an entrypoint on `:80`, you would access them as follows:
* Regular path: `http://hostname:80/foo`
* Admin panel: `http://hostname:8080/`
* Ping URL: `http://hostname:8080/ping`
However, for security reasons, you may want to be able to expose the `/ping` health-check URL to outside health-checkers, e.g. an Internet service or cloud load-balancer, _without_ exposing your admin panel's port.
In many environments, the security staff may not _allow_ you to expose it.
You have two options:
* Enable `/ping` on a regular entrypoint
* Enable `/ping` on a dedicated port
### Enable ping health check on a regular entrypoint
To proxy `/ping` from a regular entrypoint to the admin one without exposing the panel, do the following:
```toml
[backends]
[backends.traefik]
[backends.traefik.servers.server1]
url = "http://localhost:8080"
weight = 10
[frontends]
[frontends.traefikadmin]
backend = "traefik"
[frontends.traefikadmin.routes.ping]
rule = "Path:/ping"
```
The above creates a new backend called `traefik`, listening on `http://localhost:8080`, i.e. the local admin port.
We only expose the admin panel via the `frontend` named `traefikadmin`, and only expose the `/ping` Path.
Be careful with the `traefikadmin` frontend. If you do _not_ specify a `Path:` rule, you would expose the entire dashboard.
### Enable ping health check on dedicated port
If you do not want to or cannot expose the health-check on a regular entrypoint - e.g. your security rules do not allow it, or you have a conflicting path - then you can enable health-check on its own entrypoint.
Use the following config:
```toml
defaultEntryPoints = ["http"]
[entryPoints]
[entryPoints.http]
address = ":80"
[entryPoints.ping]
address = ":8082"
[backends]
[backends.traefik]
[backends.traefik.servers.server1]
url = "http://localhost:8080"
weight = 10
[frontends]
[frontends.traefikadmin]
backend = "traefik"
entrypoints = ["ping"]
[frontends.traefikadmin.routes.ping]
rule = "Path:/ping"
```
The above is similar to the previous example, but instead of enabling `/ping` on the _default_ entrypoint, we enable it on a _dedicated_ entrypoint.
In the above example, you would access a regular path, admin panel and health-check as follows:
* Regular path: `http://hostname:80/foo`
* Admin panel: `http://hostname:8080/`
* Ping URL: `http://hostname:8082/ping`
Note the dedicated port `:8082` for `/ping`.
In the above example, it is _very_ important to create a named dedicated entrypoint, and do **not** include it in `defaultEntryPoints`.
Otherwise, you are likely to expose _all_ services via that entrypoint.
In the above example, we have two entrypoints, `http` and `ping`, but we only included `http` in `defaultEntryPoints`, while explicitly tying `frontend.traefikadmin` to the `ping` entrypoint.
This ensures that all the "normal" frontends will be exposed via entrypoint `http` and _not_ via entrypoint `ping`.
