systemd 错误“无法启动服务：未正确加载单元服务：执行格式错误”

Question

我可以从 shell 执行确切的 ExecStart 命令并且它可以工作，但是由于某些原因在这个服务文件中这不起作用 - 有什么想法吗？

错误：

Failed to start previewapi.service: Unit previewapi.service is not loaded properly: Exec format error.
See system logs and 'systemctl status previewapi.service' for details.

systemd .service 文件：

[Unit]
Description = preview-api
After       = network.target

[Service]
WorkingDirectory=/srv/previewapi
ExecStart   = /usr/bin/java -jar /srv/previewapi/gn-preview-api-0.1.0-SNAPSHOT-standalone.jar

ExecStop    = kill -INT $MAINPID
ExecReload  = kill -TERM $MAINPID

# In case if it gets stopped, restart it immediately
Restart     = always

Type        = simple


[Install]
# multi-user.target corresponds to run level 3
# roughtly meaning wanted by system start
WantedBy    = multi-user.target

Ubuntu 18.04。

sudo journalctl -u previewapi 说：

Aug 15 10:00:28 ubuntu-bionic systemd[1]: /etc/systemd/system/previewapi.service:18: Executable path is not absolute:

Answer 1

问题不在于ExecStart，而在于ExecStop 和ExecReload 部分——它们也必须是绝对的。

最终版本：

[Unit]
Description = preview-api
After       = network.target

[Service]
WorkingDirectory=/srv/previewapi
ExecStart=/usr/bin/java -jar /srv/previewapi/gn-preview-api-0.1.0-SNAPSHOT-standalone.jar
ExecStop=/bin/kill -INT $MAINPID
ExecReload=/bin/kill -TERM $MAINPID

# In case if it gets stopped, restart it immediately
Restart     = always

Type        = simple


[Install]
# multi-user.target corresponds to run level 3
# roughtly meaning wanted by system start
WantedBy    = multi-user.target