Chapter 4 – Troubleshooting
Multi-Tech RouteFinder RF650VPN User Guide
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That means that if an IP-Packet from a.b.c.d port 34232 is sent to
212.5.63.4 port 80 (www) [a.b.c.d:34232 -> 212.5.63.4:80] and it reaches theRouteFinder, the
destination information will be translated into [a.b.c.d:34232 -> 192.168.100.2:81]. NAT is done
before reaching the packet filter. That means you have to set the packet filter rules.
Q13: Is it possible to have multiple IP's assigned to the external interface, and then have multiple internal
web-servers?
A13: Yes that is possible. You have to be sure that the request reaches the RouteFinder, then you can
use DNAT to redirect them to the webservers. You don't need to bind those IP addresses to the
external interface, as long as they are routed to the RouteFinder. The problem is that the IP
packets have to reach the interface. There are 2 ways to accomplish this:
1.
Bind an alias IP to the external interface, so that it answers ARP requests for this IP and the IP
packets are sent to the ARP Address of this NIC card.
(If you're ready to do some hand typing on the console you can make an IP alias on your NIC
and make a script in /etc/rc.d/rc2.d to have it run at each boot (put it at S99 to be sure). Just
don't use ifconfig to do that, as it is deprecated in 2.4 kernels.
The command to add the IP 10.0.0.3 on your
eth0
NIC card is:
ip addr add 10.0.0.3/24 broadcast 10.0.0.255 label eth0:0 dev eth0
Note that the label part is not mandatory, it's just there so that ifconfig can list your alias.
Moreover, the label name is free (you can have 'myalias' instead of eth0:0) though you should
avoid characters like '-' or '_' : ifconfig seems to get lost if you use these.)
2.
Tell the RouteFinder to send those IP packets directly to the external interface, by adding a
static routing entry. You have to do subnetworking; for example, enter the following interface
definitions and routes:
OLD:
RouteFinder:
Router Ethernet Interface:
IP: 196.126.228.65
Netmask: 255.255.255.224
Routes: none
Firewall:
RouteFinder Ethernet Interface:
IP: 196.126.228.66
Netmask: 255.255.255.224
Def GW: 196.126.228.65
NEW:
RouteFinder:
Router Ethernet Interface:
IP: 196.126.228.65
Netmask: 255.255.255.252
Routes:
196.126.228.67/255.255.255.252 -> 196.126.228.66
196.126.228.72/255.255.255.248 -> 196.126.228.66
196.126.228.80/255.255.255.240 -> 196.126.228.66
RouteFinder Ethernet Interface:
IP: 196.126.228.66
Netmask: 255.255.255.252
Def GW: 196.126.228.65
