我已经创建了以下服务文件，以在Ubuntu中将apache-airflow Web服务器作为服务启动。
[Unit]
Description=Airflow webserver daemon
[Service]
ExecStart=/bin/bash -c 'export AIRFLOW_HOME=/opt/airflow ; airflow webserver --pid /opt/airflow/webserver.pid'
Restart=on-failure
[Install]
WantedBy=multi-user.target
当我检查状态时，得到以下输出。
curw@curw-HP-Z640:/etc/systemd/system$ sudo systemctl status airflow_server
● airflow_server.service - Airflow webserver daemon
Loaded: loaded (/etc/systemd/system/airflow_server.service; disabled ; vendor preset: enabled)
Active: failed (Result: start-limit-hit) since අ 2019-02-05 08:27:30 UTC; 10s ago
Process: 32008 ExecStart=/bin/bash -c export AIRFLOW_HOME=/opt/airflow ; airflow webserver --pid /opt/airflow/webserver.pid (code=exited, status=127)
Main PID: 32008 (code=exited, status=127)
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: airflow_server.service: Unit entered failed state.
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: airflow_server.service: Failed with result 'exit-code'.
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: airflow_server.service: Service hold-off time over, scheduling restart.
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: Stopped Airflow webserver daemon.
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: airflow_server.service: Start request repeated too quickly.
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: Failed to start Airflow webserver daemon.
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: airflow_server.service: Unit entered failed state.
පෙබ 05 08:27:30 curw-HP-Z640 systemd[1]: airflow_server.service: Failed with result 'start-limit-hit'.
当我在“ ExecStart”中执行命令时，气流Web服务器正常启动。 当仅使用“气流网络服务器”时，它也能很好地工作。 我在这里做错了什么？