Wed, 29 Feb 2012 15:00:45 +0100 > -----Ursprüngliche Nachricht----- > Von: Gordan Bobic [mailto:gordan@bobich.net] > > Fiedler Roman wrote: > >> -----Ursprüngliche Nachricht----- > >> Von: Gordan Bobic [mailto:gordan@bobich.net] > >> > >> Fiedler Roman wrote: > >>>> -----Ursprüngliche Nachricht----- > >>>> Von: Gordan Bobic [mailto:gordan@bobich.net] > >>>> > >>>>> Fiedler Roman wrote: > >>>>> .... > >>>>> I'm trying to configure networking on a machine, where we cannot use > any > >>>>> private network for internal communication because I might need to > receive > >>>>> traffic from that network. So I can only use loopback, one private IP- > Range IP > >>>>> (server external IP) and I do not want to grab one public IP-range for > internal > >>>>> communication if avoidable. > >> .... > >>> Connect from guest to 127.0.1.1:80 is still remapped to 127.0.2.1, which > is > >>> guest itself. So no connection to host via lo possible. > >> You are using 127/8 subnet on the dummy device - that won't work. You > >> need a non-loopback IP range on the dummy interface, e.g. 192.168/16. > > > > Thanks for your reply. I already used configuration with non-127 dummy > interface > > and they are working. In current use case (description above), I have the > problem, > > that organization cannot tell me, which private network is not in use at their > > location. Since I cannot handle requests from their network if I bind IPs to > local > > interface, I was trying to do it without need of any other IPs than from range > > 127.0.0.0/8. > > That is most unfortunate, but I don't see a workaround - they will have > to find a suitable small private subnet in 10/8, 172.16/12 or 192.168/16 > that you can use. But since that subnet will never be routable outside > the machine itself, you can re-use it on all similar servers. > > > Things I could try: > > ... > > * Use iptables mangle or nat and mark to remap external requests from IP- > Range also bound to local interface. > > Sorry, not sure I quite follow what you think you can do here. Can you > elaborate? When I have some client with IP x accessing the machine and machine knows IP x on dummy interface, routing table entry to dummy interface will be used for e.g. tcp response packets, thus sending them to nirvana. If I mark connections depending on the interface, I should be possible to do policy routing, thus sending responses to connections from external-x back via external interface, while keeping internal-x connections internal. Roman