I was getting the following error in a container on one of my nodes.

[root@server1 ~]# iptables -t nat -F
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.

[root@server1 ~]# 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.

You can fix this by using the following commands.

[root@yoshi ~]# vzctl stop 150
[root@yoshi ~]# vzctl set 150 --iptables "iptable_nat iptable_filter iptable_mangle  ip_conntrack ipt_conntrack ipt_REDIRECT ipt_REJECT ipt_multiport  ipt_helper ipt_LOG ipt_state" --save
Saved parameters for VE 150
[root@yoshi ~]# vzctl restart 150
[root@yoshi ~]# vzctl enter 150
[root@server1 ~]# iptables -t nat -nvL
Chain PREROUTING (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target     prot opt in     out     source               destination

Chain POSTROUTING (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target     prot opt in     out     source               destination

Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target     prot opt in     out     source               destination