NAT Question

[masterleo]

I have a little problem. My network is made up of public IP addresses, IE 165.138.xxx.xxx. I want to take these workstations from the public IP Range and move them to a private IP range, IE 192.168.xxx.xxx. I have configured a windows 2003 server with 2 NICs. I configured one NIC with the 165 subnet and one with the 192 subnet. I then installed a third NIC with the 165 subnet. When I configure the server to be a nat using one of the 165 NICs as the external and the 192 as the private connected to a public everything works fine except the rest of the 165 network cannot communicate with the 192 network. I thought I would just install the third NIC and use it in the same manner as the 192 NIC, but when I do, the 192 subnet can no longer access the internet. What can I do to remedy this?

Leo

 

[Jpoandl]

Why not buy a Lynksys DSL/Cable router? Plug the WAN link into you ISP connection and all other workstations on the private side?



Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please contact

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[IMdaTEK]

How big is your network?

 

[masterleo]

My network is about 80 workstations and 8 servers. I want to be able to move the workstations to the private subnet slowly.

 

[pmf71]

I assume your company has 80 public IP addresses. I suggest the following:

get rid of 70 public IP's and keep 10 for yourself. This will save you a lot of money, i assume you pay deerly for 80 IP's.

with these 10 IP's you have left, use 1 IP to NAT all workstations that are allowed internet access to.

Nat your server to a 2nd IP address.
Nat any FTP server you may have to a 3rd.
and so on...

for example:
192.168.1.1 is your internet gateway. (static ip)
192.168.1.2 is your file server (static)
192.168.1.3 is your ftp server (static)
etc. etc.
192.168.1.20 - 192.168.1.200 is the the dhcp scope for your workstations.

Let's say you now have 10 public IP's in the range of 165.138.10.20 to 165.138.10.29

then you can NAT 192.168.1.1 to 165.138.10.20
NAT 192.168.1.2 to 165.138.10.21
NAT 192.168.1.3 to 165.138.10.22
etc. etc.
and finally NAT 192.165.1.20-192.168.1.200 to 165.138.10.29

this is a very neat way of making good use of your multiple public IP's.

But keep in mind...the internet gateway must be able to support multiple public IP's for this. WIndows server can multiple IP's to one NIC.

 

[IMdaTEK]

well put pmf71