On Friday 30 April 2004 7:20 pm, Oriol Magrané wrote: > Hello! > I'm trying to set up a firewall with two ethernets to be installed > between the internet and a pool of servers. > > I have some public ips available (a.b.c.e, a.b.c.f, a.b.c.g,...) so now > I want to map the external ip 'a.b.c.e' with the internal ip 192.168.1.100 > > The only solution I've found is to define an ip alias in the firewall itself > so that eth0:1 will respond to the external ip a.b.c.e Thus when the router > of my ISP asks "who has ip a.b.c.e?", the firewall will answer "me" and it > will process the packet and deliver it to the internal server 1. > > But this solution means defining an alias for every external ip I want > to firewall. So if I have eight servers firewalled I will need eight ip > alias in the firewall. Correct. This is not a problem. However, it is recommended that you use the new (well, not that new, but more recent) "ip" commands to add addresses to interfaces, rather than the deprecated ethn:x alias method. Try: "ip addr add a.b.c.e dev eth0" instead of the ifconfig eth0:1 command. Regards, Antony. -- "It would appear we have reached the limits of what it is possible to achieve with computer technology, although one should be careful with such statements; they tend to sound pretty silly in five years." - John von Neumann (1949) Please reply to the list; please don't CC me.