处理ftp服务器 在重启后ftp客户端不能连接访问的问题

1：环境：centos7

2：当在重启centos7 linux服务器后，再连接ftp客户端不能链接

此时需要检查以下几点：

2-1：核查ftp服务是否启动正常：

 [root@localhost ~]# service vsftpd status
 Redirecting to /bin/systemctl status  vsftpd.service
 ● vsftpd.service - Vsftpd ftp daemon
    Loaded: loaded (/usr/lib/systemd/system/vsftpd.service; enabled; vendor preset: disabled)
    Active: active (running) since Fri 2017-08-25 09:20:59 CST; 30s ago
   Process: 4517 ExecStart=/usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf (code=exited, status=0/SUCCESS)
  Main PID: 4520 (vsftpd)
    CGroup: /system.slice/vsftpd.service
            └─4520 /usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf

 Aug 25 09:20:59 localhost.localdomain systemd[1]: Starting Vsftpd ftp daemon...
 Aug 25 09:20:59 localhost.localdomain systemd[1]: Started Vsftpd ftp daemon.
 

如果是ftp服务没有启动起来：则需要执行启动命令

 service vsftpd restart

或者是设置ftp服务开机自动启动；如何设置请参考《CentOS7 搭建FTP服务器》的“七：解决 linux系统重启后 用ftp工具无法访问的问题”的内容

2-2:核查firewall防火墙是否启动正常：

 [root@localhost ~]# systemctl status firewalld.service
 ● firewalld.service - firewalld - dynamic firewall daemon
    Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: enabled)
    Active: active (running) since Fri 2017-08-25 09:00:20 CST; 25min ago
      Docs: man:firewalld(1)
  Main PID: 803 (firewalld)
    CGroup: /system.slice/firewalld.service
            └─803 /usr/bin/python -Es /usr/sbin/firewalld --nofork --nopid

 Aug 25 09:00:13 localhost.localdomain systemd[1]: Starting firewalld - dynamic firewall daemon...
 Aug 25 09:00:20 localhost.localdomain systemd[1]: Started firewalld - dynamic firewall daemon.
 

如果是firewall 服务没有启动起来，则需要手动启动

 [root@localhost ~]# systemctl restart firewalld.service
 #并核查下 启动的端口情况
 [root@localhost ~]# firewall-cmd --zone=public --list-ports
 80/tcp 8080/tcp
 #如果没有自己想要的端口，则添加端口，然后在重启firewall
 [root@localhost ~]# firewall-cmd --zone=public --add-port=21/tcp --permanent
 success
 [root@localhost ~]# systemctl restart firewalld.service
 [root@localhost ~]# firewall-cmd --zone=public --list-ports
 21/tcp 80/tcp 8080/tcp
 

2-3:核查iptables  的状态是否启动正常。

 [root@localhost ~]# service iptables status
 Redirecting to /bin/systemctl status  iptables.service
 ● iptables.service - IPv4 firewall with iptables
    Loaded: loaded (/usr/lib/systemd/system/iptables.service; enabled; vendor preset: disabled)
    Active: inactive (dead)
 [root@localhost ~]#
 

如果 没有正常启动，则需要手动启动该服务。

 [root@localhost ~]# service iptables restart
 

设置正常开机启动该服务：

 [root@localhost ~]# cd /etc/rc.d
 [root@localhost rc.d]# ls
 init.d  rc0.d  rc1.d  rc2.d  rc3.d  rc4.d  rc5.d  rc6.d  rc.local
 [root@localhost rc.d]# cat rc.local
 #!/bin/bash
 # THIS FILE IS ADDED FOR COMPATIBILITY PURPOSES
 #
 # It is highly advisable to create own systemd services or udev rules
 # to run scripts during boot instead of using this file.
 #
 # In contrast to previous versions due to parallel execution during boot
 # this script will NOT be run after all other services.
 #
 # Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure
 # that this script will be executed during boot.

 touch /var/lock/subsys/local

 /etc/init.d/nginx start
 [root@localhost rc.d]# vi  rc.local
 

在rc.loal 文件中添加  service iptables restart  确定命令

以下是 红色标注的内容是 添加的启动iptables服务的内容

 [root@localhost ~]# cd /etc/rc.d/
 [root@localhost rc.d]# ls
 init.d  rc0.d  rc1.d  rc2.d  rc3.d  rc4.d  rc5.d  rc6.d  rc.local
 [root@localhost rc.d]# cat rc.local
 #!/bin/bash
 # THIS FILE IS ADDED FOR COMPATIBILITY PURPOSES
 #
 # It is highly advisable to create own systemd services or udev rules
 # to run scripts during boot instead of using this file.
 #
 # In contrast to previous versions due to parallel execution during boot
 # this script will NOT be run after all other services.
 #
 # Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure
 # that this script will be executed during boot.

 touch /var/lock/subsys/local

 #开机默认启动nginx服务
 /etc/init.d/nginx start
 #开机重启 ip 防火墙
 

service iptables restart

 [root@localhost rc.d]#
 

如果以上3个服务都启动正常，则ftp客户端连接应该是正常的。若还有问题，则需要仔细核查