CentOS - Nov 2008 - Forward all traffic from public IP A to public IP B?

Need help.

Im trying to forward all traffic to a public server(A) to another public 
server(B) except traffic to port 22. Found this on google but cant get 
it to work. Could someone help me please.
Server A has one NIC server B has one NIC. Do i need 2 NICS in server A.

#!/bin/sh
iptables -F
iptables -F INPUT
iptables -F OUTPUT
iptables -F FORWARD
iptables -X
iptables -F -t nat
iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
iptables -P FORWARD ACCEPT

echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -A PREROUTING -i eth0 --protocol tcp --destination-port 
! 22 -j DNAT --to-destination "IP B"
iptables -t nat -A PREROUTING -i eth0 --protocol udp -j DNAT 
--to-destination "IP B"
# END

/etc/rc.d/init.d/iptables status
Table: filter
Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
num  target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination

Table: mangle
Chain PREROUTING (policy ACCEPT)
num  target     prot opt source               destination

Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
num  target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination

Chain POSTROUTING (policy ACCEPT)
num  target     prot opt source               destination

Table: nat
Chain PREROUTING (policy ACCEPT)
num  target     prot opt source               destination
1    DNAT       tcp  --  0.0.0.0/0            0.0.0.0/0           tcp 
dpt:!22 to:"IP B"
2    DNAT       udp  --  0.0.0.0/0            0.0.0.0/0           to:"IP
B"

Chain POSTROUTING (policy ACCEPT)
num  target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination



/Morten.
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Morten Sundstr?m wrote:
> Need help.
>
> Im trying to forward all traffic to a public server(A) to another public
> server(B) except traffic to port 22. Found this on google but cant get
> it to work. Could someone help me please.
Is server (B) behind server (A) ? It's been a while but last
time I checked you couldn't do forwarding to a system unless that
system was behind the system that was doing the forwarding using
normal iptables.

What I do is use a specialized utility, there are two such utilities
that I know of that handle tcp forwarding in this manor:
rinetd and redir.

The only downside is the destination system will not see any of
the original IP addresses connecting, it will only see IPs of the
system doing the forwarding.

I don't think either rinetd or redir are available in the default
CentOS installation you probably have to find them elsewhere on
the net.

As for non-TCP stuff, I don't know off the top of my head.

nate