强制重启了下，结果就发现 iptables 用不了了，提示 [root ~]# systemctl restart iptables.service Job for iptables.service failed because the control process exited with error code. See "systemctl status iptables.service" and "journalctl -xe" for details. [root ~]# systemctl status iptables.service ● iptables.service - IPv4 firewall with iptables Loaded: loaded (/usr/lib/systemd/system/iptables.service; disabled; vendor preset: disabled) Active: failed (Result: exit-code) since Fri 2016-05-20 06:32:09 UTC; 14s ago Process: 23631 ExecStart=/usr/libexec/iptables/iptables.init start (code=exited, status=1/FAILURE) Main PID: 23631 (code=exited, status=1/FAILURE)
May 20 06:32:09 vultr.guest systemd[1]: Starting IPv4 firewall with iptables... May 20 06:32:09 vultr.guest iptables.init[23631]: iptables: Applying firewall rules: iptables-restore v1.4.21: iptables-restore: unable to initialize table 'filter' May 20 06:32:09 vultr.guest iptables.init[23631]: Error occurred at line: 4 May 20 06:32:09 vultr.guest iptables.init[23631]: Try `iptables-restore -h' or 'iptables-restore --help' for more information. May 20 06:32:09 vultr.guest iptables.init[23631]: [FAILED] May 20 06:32:09 vultr.guest systemd[1]: iptables.service: main process exited, code=exited, status=1/FAILURE May 20 06:32:09 vultr.guest systemd[1]: Failed to start IPv4 firewall with iptables. May 20 06:32:09 vultr.guest systemd[1]: Unit iptables.service entered failed state. May 20 06:32:09 vultr.guest systemd[1]: iptables.service failed.