# Varnish

As described in the [reverse proxies documentation section](../../up-and-running/reverse-proxies), you need to bypass Varnish when profiling. You can do this in your VCL file, based on the sample below.

## VCL Sample

```vcl
acl profile {
   # Authorized IPs, add your own IPs from which you want to profile.
   "x.y.z.w";
}

sub vcl_recv {
  if (req.esi_level > 0) {
    # ESI request should not be included in the profile.
    # Instead you should profile them separately, each one
    # in their dedicated profile.
    # Removing the Blackfire header avoids to trigger the profiling.
    # Not returning let it go trough your usual workflow as a regular
    # ESI request without distinction.
    unset req.http.X-Blackfire-Query;
  }

  # If it's a Blackfire query and the client is authorized,
  # just pass directly to the application.
  if (req.http.X-Blackfire-Query && client.ip ~ profile) {
    return (pass);
  }
}
```