我有一个 Ubuntu 16.04 服务器，我在其中安装了 Caddy 作为 HTTP 服务器。我也有一些指向该服务器的子域。我将这些子域之一指向错误的 IP，现在我有：
caddy.service: Service hold-off time over, scheduling restart.
我尝试重新启动服务，但得到相同的结果。还修改了/lib/systemd/system/caddy.service文件，现在服务块看起来像：
[Service]
Restart=on-failure
StartLimitInterval=86400
StartLimitBurst=500000
RestartSec=3
我重新启动了守护程序，但结果相同。现在我得到：
Activating privacy features... 2018/04/17 23:32:24 [INFO][sub.domain.com] acme: Obtaining bundled SAN certificate
Apr 17 23:32:24 ubuntu-apps caddy[22434]: 2018/04/17 23:32:24 [INFO][] Certificate written to disk: /etc/ssl/caddy/acme/acme-v02.api.letsencrypt.org/sites/.crt
Apr 17 23:32:24 ubuntu-apps caddy[22434]: 2018/04/17 23:32:24 open /etc/ssl/caddy/acme/acme-v02.api.letsencrypt.org/sites/sub.domain.com/sub.domain.com.crt: no such file or directory
Apr 17 23:32:24 ubuntu-apps systemd[1]: caddy.service: Main process exited, code=exited, status=1/FAILURE
Apr 17 23:32:24 ubuntu-apps systemd[1]: caddy.service: Unit entered failed state.
Apr 17 23:32:24 ubuntu-apps systemd[1]: caddy.service: Failed with result 'exit-code'.
Apr 17 23:32:25 ubuntu-apps systemd[1]: caddy.service: Service hold-off time over, scheduling restart.
可能是让我们加密拒绝我的那个吗？我还能做些什么来强制重启？