Adding IPs from another server locally?

Linux303 · 11-27-2011, 12:04 AM

Hey Guys,

I have a customer who has a server with many IPs from other Linux boxes bound locally. I don't have root access so I'm not able to dig in.

IP-IP Tunneling seems to only work with private IPs. Please correct me if I'm wrong.

Another idea I have is that some sort of tunneling is installed. I still don't understand how the IPs are bound to eth0 though.

Thoughts?

TIA

ccolumbu · 11-28-2011, 04:47 PM

I am not sure there is a question here.
You can bind multiple IPs to a single card easily, and as far as limiting the tunneling this can be done from iptables.

What is the question you need answered?

Linux303 · 11-28-2011, 10:16 PM

Sorry as I had a hard time explaining.

So, Server is at ISP A and has 1 public IP addy. Let's say it is 100.100.100.1

Now, they have another server at ISP B with the IP address of 200.200.200.1

In the scenario I'm seeing, the server at ISP A has both 100.100.100.1 and 200.200.200.1 bound to eth0. When we want to use 200.200.200.1, the server routes the traffic through the server at ISP B seamlessly.

Thoughts?

TimothyEBaldwin · 11-29-2011, 03:49 PM

Tunnels do run with public IP address, but you will 2 IP addresses from ISP B to do this without NAT. To get the replies back though the tunnel you will need to route by source address. You can proxy ARP to mimic 2 directly connected computers.

But why not change the DNS record?