Following the install of CSF (ConfigServer Security & Firewall) on some servers, you may experience the following error message when executing a CSF restart:
*WARNING* Binary location for [HOST] [/usr/bin/host] in /etc/csf/csf.conf is either incorrect, is not installed or is not executable
If this happens to you, don't worry, it's simply that you are missing a package that CSF requires to run correctly. To resolve this problem, please install the following package:
yum install bind-utils -y
Or, if you're running Ubuntu, Debian or some other apt-based distro, try this instead:
apt-get install dnsutils -y
Once this is done, you should be able to restart CSF without seeing the above error message.
csf -r