Enable Iptables Modules for a VPS

Below was the error while trying to install CSF in one of the OpenVz containers:

    ----------------------------------error--------------------------------
    [root@abc ~]# perl /etc/csf/csftest.pl
    Testing ip_tables/iptable_filter...OK
    Testing ipt_LOG...FAILED [ 4294967295] - Required for csf to function
    Testing ipt_multiport/xt_multiport...FAILED [FATAL Error: iptables: Unknown error 4294967295] - Required for csf to function
    Testing ipt_REJECT...OK
    Testing ipt_state/xt_state...FAILED [FATAL Error: iptables: Unknown error 4294967295] - Required for csf to function
    Testing ipt_limit/xt_limit...FAILED [FATAL Error: iptables: Unknown error 4294967295] - Required for csf to function
    Testing ipt_recent...FAILED [Error: iptables: Unknown error 4294967295] - Required for PORTFLOOD and PORTKNOCKING features
    Testing xt_connlimit...FAILED [Error: iptables: Unknown error 4294967295] - Required for CONNLIMIT feature
    Testing ipt_owner/xt_owner...FAILED [Error: iptables: Unknown error 4294967295] - Required for SMTP_BLOCK and UID/GID blocking features
    Testing iptable_nat/ipt_REDIRECT...FAILED [Error: iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?)] - Required for MESSENGER feature
    Testing iptable_nat/ipt_DNAT...FAILED [Error: iptables v1.3.5: can't initialize iptables table `nat': Table does not exist (do you need to insmod?)] - Required for csf.redirect feature
    ---------------------------------------------------------------



Enable Iptables Modules for a VPS:-

How to configure NAT with iptables on a VPS.

NAT ( network-address-translation ) with iptables  helps us in how to select the packets we want to mangle. We can easily configure NAT on a OpenVZ VPS by following the below steps.

Lets first consider a VPS in which NAT is not enabled. Trying to POSTROUTE from VPS throws you errors.

iptables -t nat -A POSTROUTING -s 10.9.0.0/24 -o venet0 -j SNAT –to 111.140.170.134

or iptables -t nat -nvL

iptables v1.3.5: can’t initialize iptables table `nat’: Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.

To Enable NAT :

* Login to Node server.

Check vzcinfiguration file to find whether NAT is enabled or not.

grep -i iptables /etc/vz/vz.conf

You will get