Red Hat and Broken IPMasquerading

The-Pheon asks "Ok. I've read the FAQs, scoured the Linux newsgroups searching for information about ipmasqadm and I still can't get simple port forwarding to work on RedHat6. Any suggestions are greatly appreciated. The scenario: Standard Red Hat 6.0, Kernel 2.2.12, and ipchains-1.3.8. External is ip_aliased with a legal dns addresses, Internal is a single reserved address and network, IP masquerading is configured and working for intenal -> external connections. This seems like it should be simple. To forward a simple telnet I use: /sbin/modprobe ip_masq_portfw; /usr/sbin/ipmasqadm portfw -a -P tcp -L x.x.x.x 23 -R 192.168.1.12 23 The result: A telnet sessions to x.x.x.x (from a completely outside source) just hangs. Closer investigation shows that port forward is working -- sort of." More details are available if you hit the link.

"I use the following:

/sbin/ipchains -P forward DENY and then

/sbin/ipchains -A forward -s 192.168.32.0/24 -d 0.0.0.0/0 -j MASQ

IP forwarding is enabled in /proc/sys/net/ipv4/ip_forward

The kernel and modules have been rebuilt with all the relevant options set.

The netstat output of 192.168.1.12 shows a SYN_RECV connection from the remote address. Also, netstat -M on masquerading Linux box shows a correct entry for the translation. Nevertheless, the conversation is never completed and the session just hangs. I've also tried adding several ipchains, in particular:

ipchains -I forward -p tcp -s 192.168.32.20/32 23 -j MASQ

-- with no luck.

Is this just a fluke in RedHat? has anyone else ever successfully get ipmasqadm and portfw working with Red Hat? "