TNS Listener Connecting issue through ISA 2006

Question

We have Oracle 8i installed on?a Win XP Professional workstation, and pretty much as it comes - we haven't?changed many config. parms.
We have a basic ISA 2006 firewall, and when the Oracle machine is not behind it we can contact it without ay problems. However, when we put the machine behind the firewall we can 'tnsping' it, but cannot contact it with SQL*Plus
I have 1521 Port Opened in my ISA 2006 Firewall
i set USE_SHARED_SOCKET = TRUE under Windows registry on Oracle Server, Firewall & on the Client.
My tnsnames.ora is somewhat like this...
L.world =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(COMMUNITY = oracle.world)
(PROTOCOL = TCP)
(Host = 127.0.0.1)
(Port = 1521)
(CONNECT_DATA = (SID = ORCL)
(SERVER = DEDICATED)
M.world =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS =
(COMMUNITY = oracle.world)
(PROTOCOL = TCP)
(Host = 213.XXX.XXX.XXX)
(Port = 1521)
(ADDRESS =
(COMMUNITY = oracle.world)
(PROTOCOL = TCP)
(Host = 213.XXX.XXX.XXX)
(Port = 1526)
(CONNECT_DATA = (SID = ORCL)
(SERVER = DEDICATED)
I've run a trace on SQL*Net and the problem seems to be as follows:
1. The client contacts the server using its external IP address.
2. Oracle responds with a packet which contains the?INTERNAL IP address of the machine. (i.e. the machines IP address on our local intranet)
3. The client attempts to contact Oracle using the Oracle machine's internal intranet IP address.?Of course this fails because only the external address is valid outside the firewall.
4. SQL*Plus responds TNS-12535: TNS:operation timed out???
Can anyone suggest ....
what to be done now

Answer 1

I just went through something similar. Have you tried the setting to make request appear to come from the ISA server rather than the original client in the configuration rule? I'm not sure how you examined the packet, so I can't say my situation was exactly the same, but it sounds very similar and that solved it for me.