#!/bin/bash
# 向一个临时文件中写入配置的内容,两种形式service和systemctl
sudo cat >/tmp/mysql-exporter-systemctl<<EOF
[Unit]
Description=Mysql Exporter
After=network.target
[Service]
ExecStart= ...
[Install]
WantedBy=default.target
EOF
sudo cat >/tmp/mysql-exporter-service<<EOF
#!/bin/bash
case "\$1" in
start)
...
echo \$!>/var/run/[servicename].pid
;;
stop)
sudo kill \`cat /var/run/[servicename].pid\`
sudo rm -f /var/run/[servicename].pid
;;
restart)
\$0 stop
\$0 start
;;
status)
if [ -e /var/run/[servicename].pid ]; then
echo [servicename] is running, pid=\`cat /var/run/[servicename].pid\`
else
echo [servicename] is NOT running
exit 1
fi
;;
*)
echo "Usage: \$0 {start|stop|status|restart}"
esac
exit 0
EOF
function service_conf(){
# 判断使用那种形式的配置内容
if [ -x /usr/bin/systemctl ]; then
sudo mv /tmp/mysql-exporter-systemctl /usr/lib/systemd/system/[servicename].service
sudo chmod 754 /usr/lib/systemd/system/[servicename].service
sudo systemctl daemon-reload
sudo systemctl enable [servicename].service
elif [ -x /bin/systemctl ]; then
sudo mv /tmp/mysql-exporter-systemctl /lib/systemd/system/[servicename].service
sudo chmod 754 /lib/systemd/system/[servicename].service
sudo systemctl daemon-reload
sudo systemctl enable [servicename].service
else
sudo mv /tmp/mysql-exporter-service /etc/init.d/[servicename]
sudo chmod 755 /etc/init.d/[servicename]
fi
}
service_conf
这个脚本使用于多个操作系统
Systemd 默认从目录/etc/systemd/system/读取配置文件。但是,里面存放的大部分文件都是符号链接,指向目录/usr/lib/systemd/system/,真正的配置文件存放在那个目录。
systemctl enable命令用于在上面两个目录之间,建立符号链接关系。
$ sudo systemctl enable clamd@scan.service
# 等同于
$ sudo ln -s '/usr/lib/systemd/system/clamd@scan.service' '/etc/systemd/system/multi-user.target.wants/clamd@scan.service'
如果配置文件里面设置了开机启动,systemctl enable命令相当于激活开机启动。
与之对应的,systemctl disable命令用于在两个目录之间,撤销符号链接关系,相当于撤销开机启动。