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[Shorewall-users] one-to-one nat and internal hosts communicating trough external public IP

From: Stephane Bouvard <ml_at_nospam>
Date: Thu Jan 12 2012 - 15:36:07 GMT


Yes, i've read the differents FAQ, and i fully understand them...

But i cannot use proxy arp : my hosts are dedicated servers hosted on the cloud with only one vlan available (my hoster refuse to give more than 1 vlan), and thus my two zones net & loc are connected to the same vlan, and proxy arp need two layer 2 separated network. Split DNS are not a solution nope, because i do not have control on the DNS (i host customers VPS on my servers, my customers use their own DNS on their VPS, and i cannot give to one customer the list of domains used by the others customers).

As i do not want that loc->loc traffic appear to originate on the firewall, i'm testing another solution that i would like to explain here, to see if you think there could be some problems i've not yet detected...

Thus to resume :

# net (eth0) : - gateway (router of my hoster)
# loc (eth1) :

# interfaces
net eth0 detect blacklist
loc eth1 detect routeback

# nat eth0 no no eth1 no no eth0 no no eth1 no no

To explain : i declare twice the one-to-one rules, once on the net interface, like documented, but also once on the loc interface... i do *not* declare any masq rule

It seems to work : when try to reach, receive the connection originated from, it's what i want...

But is there any reason i should not use this method ? I've not found this solution documented in the FAQ of Shorewall, and thus i ask myself if i miss something...

Thanks for any tips on this subject :)

-- Bien à vous... _ (_' Un problème de serveur ? Diagnostic rapide et pro pour 25 euros ! ,_)téphane Bouvard ------------------------------------------------------------------------------ RSA(R) Conference 2012 Mar 27 - Feb 2 Save $400 by Jan. 27 Register now! _______________________________________________ Shorewall-users mailing list