RHEL 6 gateway config

Hi,

I am trying to configure a RHEL 6 server as a gateway to the internet for an inner server.

The gateway server (server1) has 2 NICs:

em1 192.168.168.56/24

em2 20.249.6.135/24

default gateway 192.168.168.254

The inner server (server2) has:

eth1 20.249.6.136/24

default gateway 20.249.6.135

I have forwarding allowed:

# cat /proc/sys/net/ipv4/ip_forward
1

# iptables -L -n -v

Chain FORWARD (policy ACCEPT 79 packets, 6636 bytes)

I can ping and ssh from server1 to server2, and vice-a-versa.   I cannot ping the ultimate gateway and beyond 192.168.168.254.

You can see from the FORWARD accept packets that the pings are arriving at server2.

I have tried to configure SNAT with this unsuccessfully:

iptables -t nat -A POSTROUTING -o em1 -j MASQUERADE

Thanks for any help you can provide.