CSF on Virtuozzo

A installation of CSF performed on a VM (based on Virtuozzo) was no longer accepting traffic to VM. In order to correct this I created the csfpre.sh file (/etc/csf/csfpre.sh) – and set the following set of rules – are executed before all other statements when CSF is started:

iptables -A INPUT -i venet0 -j ACCEPT
iptables -A OUTPUT -o venet0 -j ACCEPT
iptables -A FORWARD -j ACCEPT -p all -s 0/0 -i venet0
iptables -A FORWARD -j ACCEPT -p all -s 0/0 -o venet0

This is required to allow the traffic through your virtual ethernet device (venet0). Restart the firewall and everything should work once again as expected.

dig, host, and nslookup

BIND Utilities is a collection of the client side programs that are included with BIND. The BIND package includes the client side programs nslookup, dig and host. If you install BIND server, these programs will be installed automatically. In the situation when you are not looking on having the BIND server installed, but you would like to install the client side applications (dig, host, and nslookup) this can be done by installing only the bind-utils package:

$ host
-bash: host: command not found

$ dig
-bash: dig: command not found

$ nslooup
-bash: nslookup: command not found

yum install bind-utils

$ dig -v
DiG 9.7.3-P3-RedHat-9.7.3-2.el6_1.P3.3