Reposting because of lack of subject line.  Apologies to all on the list.
-Jeff


I've been trying off and on for several days to get ipf installed on my Solaris 8 box to test out a particular configuration. I had previously convinced myself from reading the howto that my application could be accomplished, but now I'm not so sure. If anyone who is much more intimate with this than I am could guide me along, I'd appreciate it.

The crux of the issue is whether I can use ipf/ipnat to change the
destination address of an outbound packet and the source address of an
inbound packet.  This is kind of the opposite of what traditional NAT does.

Here's the long story.  I have a Sun Ultra 10 running Solaris 8 which is
running a large software application.  This application communicates
through a large IP network to a board running VxWorks which resides in a
compact PCI shelf.  This card in turn communicates through a private IP
network (over a compactPCI midplane) to other VxWorks cards using their
private IP addresses.  Certain software requires the Sun to directly
address the privately addressed cards by using the main card as a
router.  Here's the picture:

Sun                            VxWorks
                            main board
hme0                             if1
192.168.0.9 ----(IP cloud)----192.168.100.1
                             routes to           other VxWorks
                               if2                   board
                            10.20.1.20-------------10.20.1.7

So the routers in the IP cloud know that to get to 10.20.1.0 subnet, the
packet needs to go through the "router" 192.168.100.1.

Now, I have a situation where the routing in the IP cloud cannot/will
not be done, so I am trying to find a workaround.

My idea was to get extra addresses on the 192.168.100.x subnet to use as
aliases for the private addresses.  Let's say that I have 192.168.100.7
as an alias for 10.20.1.7.  The software application on the Sun would
try to send its packet to 10.20.1.7, and I'd like to use ipnat to change
the destination from 10.20.1.7 to 192.168.100.7.  The packet then gets
sent out and routed across the network to a newly inserted device which
has an ethernet port on the 192.168.100.x network with 192.168.100.7 as
an IP.  It would use ipnat to change that back to 10.20.1.7, and send it
out a second port over to 192.168.100.1.

Visually:

Sun                             VxWorks
                             main board
hme0                              if1
192.168.0.9-----(IP cloud)-[ ]--192.168.100.1
          ^               ^   routes to            other VxWorks
          |               |     if2                   board
          |               |  10.20.1.20-------------10.20.1.7
      run ipnat           |
        here           new device
     to change         runs ipnat
     destination       here to change
                        origin

So is this the type of application that ipf/ipnat can do gracefully and
simply?  Or is this in some profound way different than all of the other
applications I've been reading about in the various documentation and
emails on the subject?

Thanks,
Jeff Gilles

_________________________________________________________________
Check out Election 2004 for up-to-date election news, plus voter tools and more! http://special.msn.com/msn/election2004.armx




Reply via email to