static 1:1 nat did not work

[Guenter.Sprakties at team4.de]

Hello,

'cause I didn't get iptables nat to work, I switch back to an old 2.4 
kernel and iproute2.

Three network segments, one intranet 172... , one dmz 192. .... one 
extranet 212.a.b.... 

iproute2 setting is simple:

        # Fast-NAT für DMZ-Intranet
        ip rule add from 192.168.2.20 nat 172.31.27.20 to 172.31.24.0/24 
table dmz prio 100
        ip route add nat 172.31.27.20 via 192.168.2.20 table local
         # Fast-NAT für DMZ-Internet (hier Extranet :-))
        ip rule add from 192.168.2.20 nat 212.a.7b.c table dmz prio 200
        ip route add nat 212.a.b.c via 192.168.2.20 table local
        # Defaultroute einrichten
        ip route add default via 212.117.70.33
        ip route flush cache

ping from 172... to 172.31.27.20 is ok, in iptables we see
 
       ping  src 172. ... 10   -> 192.168.2.20
       pong src 192.168.2.20 -> 172. ... 10

Now we activated a apache on our test-dmz system and tried to GET the site 
from intern.
Surprisire, it didn't work. From the one side, we saw all tcp-packet in 
the iptables log, but in the webserver log nothing happens and we got the 
message in our browser 'server not found'. With the not natted ip of 
192.168.2.20, everything is fine. For testing, we didn't start iptables at 
all an dused ip_forward alone, again, we did not get the server while 
there was definitive no  rule against routing. And, like i said at the 
strart, ICMP work fine.

Any idea? Or wrong group b'cause an apache problem?

Greetings,

Dr. Günter Sprakties
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