在CentOS6中写服务脚本，需要放在/etc/init.d/目录下，且脚本编写较复杂在。而在CentOS7中写服务脚本，只需要按照格式编写即可。
存放位置
/usr/lib/systemd/system #系统服务，开机不需要登录就能运行的程序（可以用于开机自启）
/usr/lib/systemd/user #用户服务，需要登录后才能运行程序
服务脚本编写
服务脚本一般以xxx.service命名，且脚本中分为三部分：[Unit]、[Service]、[Install]
示例
vim /usr/lib/systemd/system/xxx.service
[Unit]
Description=test
After=network.target
Before=xxx.service
[Service]
Type=forking # 表示后台运行模式。
PIDFile=/usr/local/test/test.pid
ExecStart=/usr/local/test/bin/startup.sh
ExecReload=xxx
ExecStop=xxx
Restart=on-failure
PrivateTmp=true
[Install]
WantedBy=multi-user.target
nginx脚本编写
[root@n1 ~]# vim /usr/lib/systemd/system/nginx.service
[Unit]
Description=nginx
After=syslog.target network-online.target remote-fs.target nss-lookup.target
Wants=network-online.target
[Service]
Type=forking
PIDFile=/var/run/nginx.pid
LimitAS=infinity
LimitRSS=infinity
LimitCORE=infinity
LimitNOFILE=65536
ExecStartPre=/usr/local/nginx/sbin/nginx -t
ExecStart=/usr/local/nginx/sbin/nginx
ExecReload= /usr/local/nginx/sbin/nginx -s reload
ExecStop=/bin/kill -s QUIT $MAINPID
Restart=on-failure
PrivateTmp=true
[Install]
WantedBy=multi-user.target
如果需要env,就可以
Systemd 需要在service文件中引入环境变量
[Service]
EnvironmentFile=/usr/lib/systemd/system/serviceEnvironment
或者
[Service]
Environment="SECRET=pGNqduRFkB4K9C2vijOmUDa2kPtUhArN"
Environment="ANOTHER_SECRET=JP8YLOc2bsNlrGuD6LVTq7L36obpjzxd"
命令使用：
- 启动、停止服务
systemctl start nginx.service
systemctl stop nginx.service - 重启服务
systemctl reload nginx.service #服务启动时重启有效
systemctl restart nginx.service - 查看nginx服务状态
systemctl status nginx.service - 添加服务到开机自启、取消开机自启
systemctl enable nginx.service
systemctl disable nginx.service
配置一个自定义脚本服务
这里写一个rsync+inotify的脚本服务（注意：此脚本是在centos6直接拿过来用的，在centos6可以直接使用chkconfig管理，这里只是测试，勿喷）
1、创建脚本目录（为什么不要centos自带的脚本目录呢？这是为了方便管理）
mkidr -p /server/scripts/sync.sh
vim /server/scripts/sync.sh
2、脚本代码
#!/bin/bash
#chkconfig: 2345 38 46
. /etc/init.d/functions
if [ $# -ne 1 ]
then
echo "usage: $0 {start|stop|status}"
exit 1
fi
case "$1" in
start)
if [ -e "/var/run/inotify.pid" ]
then
action "inotify service start fail" /bin/false
echo "sync server is running......"
sleep 1
exit 1
fi
/bin/bash /server/scripts/inotify.sh &
`ps -ef|grep "inotifywait"|grep -v "grep"|awk '{print $2}'` >/var/run/inotify.pid
if [ `ps -ef|grep inotify|wc -l` -gt 2 ]
then
action "inotify service is started" /bin/true
else
action "inotify service is started" /bin/false
fi
;;
stop)
if [ `ps -ef|grep inotify|grep -v grep|wc -l` -a -e "/var/run/inotify.pid" ]
then
rm -f /var/run/inotify.pid >/dev/null 2>&1
pkill inotifywait
else
action "inotify service stop fail" /bin/false
echo "sync server is not running"
sleep 1
exit 1
fi
sleep 1
if [ `ps -ef|grep inotify|grep -v grep|wc -l` -eq 0 -a ! -e "/var/run/inotify.pid" ]
then
action "inotify service is stoped" /bin/true
else
action "inotify service is stoped" /bin/false
fi
;;
status)
if [ `ps -ef|grep inotify|wc -l` -gt 2 ]
then
action "inotify service is running"
else
action "inotify service is stoped"
fi
;;
*)
echo "usage: $0 {start|stop|status}"
exit 1
esac
3、添加注册脚本服务文件(vim /usr/lib/systemd/system/syncd.service)，文件内容如下
[Unit]
Description="这是rsync+inotify实时同步服务"
After=network.target remote-fs.target nss-lookup.target
[Service]
Type=forking
ExecStart=/bin/sh /server/scripts/sync.sh start
ExecReload=/bin/sh /server/scripts/sync.sh restart
ExecStop=/bin/sh /server/scripts/sync.sh stop
KillSignal=SIGQUIT
TimeoutStopSec=5
KillMode=process
PrivateTmp=true
[Install]
WantedBy=multi-user.target
4、运行systemctl start syncd命令启动服务
systemctl daemon-reload
systemctl start syncd
以下是改进后的服务模版
#!/bin/bash
# chkconfig: 2345 10 90
# description: myservice ....
- 根据自己的情况替换some-progress为自己的进程名字
. /etc/init.d/functions
if [ $# -ne 1 ]
then
echo "usage: $0 {start|stop|restart|status}"
exit 1
fi
start() {
if [ -n "$(ps -ef | grep "/some-progress"|grep -v grep|grep -v "log"|grep -v "some-progress.sh")" ];then
action "some-progress service start fail" /bin/false
echo "some-progress is running......"
sleep 1
exit 1
fi
cd /usr/local/dns/bin/
nohup ./some-progress >/dev/null 2>&1 &
ps -ef|grep "/some-progress"|grep -v "grep"|grep -v "log"|grep -v "some-progress.sh"|awk '{print $2}' >/var/run/some-progress.pid
if [ `ps -ef | grep "/some-progress"|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -eq 1 ];then
action "some-progress service is started" /bin/true
else
action "some-progress service is started" /bin/false
fi
}
stop() {
if [ `ps -ef | grep "/some-progress"|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -a -e "/var/run/some-progress.pid" ]
then
rm -f /var/run/some-progress.pid >/dev/null 2>&1
ps -ef|grep "/some-progress"|grep -v "grep"|grep -v "log"|grep -v "some-progress.sh"|awk '{print $2}'|xargs kill -9
else
action "some-progress service stop fail" /bin/false
echo "some-progress service is not running"
fi
sleep 1
if [ `ps -ef|grep some-progress|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -eq 0 -a ! -e "/var/run/some-progress.pid" ]
then
action "some-progress service is stoped" /bin/true
else
action "some-progress service is stoped" /bin/false
fi
}
case "$1" in
start)
start
;;
stop)
stop
;;
restart)
stop
start
;;
status)
if [ `ps -ef|grep some-progress|grep -v grep|grep -v "log"|grep -v "some-progress.sh"|wc -l` -eq 1 ]
then
action "some-progress service is running"
else
action "some-progress service is stoped"
fi
;;
*)
echo "usage: $0 {start|stop|restart|status}"
exit 1
esac