应用示例

概述

参考:

开机建立远程隧道

[Unit]
Description=Remote SSH

[Service]
ExecStart=/bin/ssh -N -R 20001:localhost:22 root@10.253.26.241
Restart=on-failure
RestartSec=10

[Install]
WantedBy=network.target

让 Service 使用环境变量

[Unit]
Description=UnitDemo

[Service]
EnvironmentFile=/etc/default/demo
ExecStart=/usr/local/bin/unit-demo.sh

[Install]
WantedBy=multi-user.target
~]# cat /etc/default/demo
DEMO=DesistDaydream
~]# cat /usr/local/bin/unit-demo.sh 
#!/bin/bash
#
while :
do
    echo $DEMO
    sleep 5
done

启动 Service 后,可以看到如下输出

Aug 01 14:14:45 centos7-2009 systemd[1]: Started Foo.
Aug 01 14:14:45 centos7-2009 unit-demo.sh[8901]: DesistDaydream
Aug 01 14:14:50 centos7-2009 unit-demo.sh[8901]: DesistDaydream
Aug 01 14:14:55 centos7-2009 unit-demo.sh[8901]: DesistDaydream
Aug 01 14:15:00 centos7-2009 unit-demo.sh[8901]: DesistDaydream