It’s pretty easy to build a Linux router even on a virutal machine. I’ve used virtualbox to create a LAN NAT router with DHCP services using webmin. However, I’m not going to cover on how to use a virtualbox VM 🙂
Let’s create the NAT Router first.
On Webmin go to Networking > Network Configuration > Routing and Gateways
Fig-1
- Select right ethernet interface on Default Route
- Fillup the correct gateway
- Enable “Act as a Router”
On Networking > Linux Firewall > Select “Reset Firewall”
- Do network address translation on external interface: <select your WAN interface>
- Click Setup Firewall
- Finally “Apply Configuration”
Your Linux NAT router is now ready 🙂
Now Setting up simple DHCP Server using Webmin
Install DHCP server
Option A): Centos 5.8
# yum install dhcp
Set the DHCP service to start on boot
# chkconfig dhcpd on
Start DHCP service
# service dhcpd start
Option B): Ubuntu 10.04
sudo apt-get install dhcp3-server
2.- Setting up
My network design is the following:
Network name: Intranet Network adsress: 192.168.0.0 Netmask: 255.255.255.0 Address range: 192.168.0.75 – 192.168.0.150 (DHCP server can give 75 IPs) Domain: mydomain.intranet Default routers: 192.168.0.1 Broadcast address: 192.168.0.255 DNS servers: 192.168.0.21 80.58.61.250 192.168.0.21 -> DNS Server Local (our own DNS Server, within our network) 80.58.61.250 -> DNS Server External (ISP company)
Now do the following:
- Access webmin from any browser (use your own IP number): https://your_IP:10000
- First refresh modules: Webmin -> Webmin Configuration -> Refresh Modules
- Servers -> DHCP Server – > Add a new subnet.
- Fill boxes and click create
- Servers -> DHCP Server -> Edit Client Options
- Fill boxes (Antención with dot at the end of intranet!!!!!!!!)
- on the same screen mark Interim in “DNS update style” and click save
- Finally start DHCP server
