Binary location for [/usr/bin/host] in csf.conf is either incorrect, is not installed or is not executable

重新加载CSF(csf -r)时可能会发生以下错误：

*WARNING* Binary location for [HOST] [/usr/bin/host] in /etc/csf/csf.conf is either incorrect, is not installed or is not executable
*WARNING* Missing or incorrect binary locations will break csf and lfd functionality

在这种情况下，CSF安装在CentOS 7服务器上，/usr/bin下没有任何"主机"可执行文件。

要解决此问题，只需安装Bind Utilities(bind-utils)提供的缺少的软件包：

yum install bind-utils