下面一些端口与服务都是大家经常能够在centos7用到的，如果缺乏环境的话可以去3A服务器看看！
Linux 常见端口
FTP 21
SSH 22
Telnet 23
http/ngix 80
HTTPS 443
SQL Server 1433
SQL Server 1434
Oracle 1521
MySQL 3306
Linux 常见服务启动
sshd服务 systemctl restart sshd
network服务 systemctl restart network
mysql服务 systemctl restart mysql 或者 systemctl restart mariadb
ftp服务 systemctl restart vsftpd
tomcat服务 systemctl restart tomcat
http服务 systemctl restart httpd
nginx服务 systemctl restart nginx
