Setting up a virtual machine network

Windows 2008 Server Core

Windows 2008 Server Core edition does not provide a graphical interface to configure the system network. The configuration needs to be done manually by using the command prompt. You need to run the following commands. The IP addresses that are used in this example need to be replaced with the IP addresses from your IP Blocks. These commands work with older versions of Windows Server that include the netsh command.

Example public IP block – 192.0.2.0/29

• IP address – 192.0.2.2
• Gateway – 192.0.2.1
• Subnet Mask – 255.255.255.248

Example private IP block – 10.0.0.0/29

• IP address – 10.0.0.2
• Gateway – 10.0.0.1
• Subnet Mask – 255.255.255.248

Public Network

This command creates the public network to connect your server to the internet.

• Netsh interface ip set address name=”Local Area Connection 2” static 192.0.2.2 255.255.255.248 192.0.2.1

These commands create the DNS entries. If you are not using the private network, you need to replace these IP addresses with working DNS servers

• Netsh interface ip add dns “Local Area Connection 2” 10.0.80.11
• Netsh interface ip add dns “Local Area Connection 2” 10.0.80.12

Private Network

The following two commands configure the private network and create the persistent route for the private network. The persistent route provides your private network access to the entire private network. Access includes the DNS servers in the public network configuration. Note: No gateway is assigned to the private network.

• Netsh interface IP set address name=”Local Area Connection” static 10.0.0.2 255.255.255.248
• Route add 10.0.0.0 mask 255.0.0.0 10.0.0.1 -p

Windows 2003 Standard and Enterprise

You can use Windows 2003 to configure networking by using either the command line or the graphical user interface. If want to use the command line, see the configuration instructions for Windows 2008 Server Core. These instructions also work for Windows 2003. The instructions for using the graphical interface are provided here. The IP addresses that are used in this example need to be replaced with the IP addresses from your IP Blocks.

Example private IP block – 10.0.0.0/29

• IP address – 10.0.0.2
• Gateway – 10.0.0.1
• Subnet Mask – 255.255.255.248

Windows 2008 Web, Standard, Enterprise, and Datacenter

If you have Windows 2008, you configure networking by using either the command prompt or the graphical user interface. If you intend to use the command prompt, refer to the configuration instructions for Windows 2008 Server Core. These instructions work for all 2008 servers. The instructions for using the graphical interface are provided here. The IP addresses that are used in this example need to be replaced with the IP addresses from your IP Blocks.

Example private IP block – 10.0.0.0/29

• IP address – 10.0.0.2
• Gateway – 10.0.0.1
• Subnet Mask – 255.255.255.248

Open your network configurations

1. Go to Start Menu > Settings > Control Panel
2. Open Network and Sharing Center and click Manage network connections

• If you installed two network adapters, you see “Local Area Connection” and “Local Area Connection 2”.

Public Network

The following instructions provide detailed steps on configuring the public network through the windows graphical interface.

1. Right-click Local Area Connection > Properties.
2. Select Internet Protocol Version 4 (TCP/IPv4) Properties.
3. Go to General > Use the following IP address: and enter your public IP address, subnet mask, and gateway.
4. Select Use the following DNS server addresses:. If you are configuring the private network, use the following DNS Servers. If you are not configuring the private network, you need to provide DNS servers
   • Preferred DNS server: 10.0.80.11
   • Alternate DNS server: 10.0.80.12
5. Click OK

Private Network

1. Right-click on Local Area Connection 2 > Properties and select Internet Protocol Version 4 (TCP/IPv4) > Properties.
2. Go to General > Use the following IP address:, enter your private IP address and subnet mask, and click OK.
3. Click OK again to close the network configuration window.

To provide access to the entire private network which includes the DNS servers, you need to add a custom route to the server.

1. Go to Start > Run and enter “cmd” and click OK
2. Run the following command: Note: Replace the gateway address (10.0.0.1) with your private IP block gateway.
   • route add 10.0.0.0 mask 255.0.0.0 10.0.0.1 –p

RedHat, Fedora, and CentOS

Configuring the network on RedHat, Fedora and CentOS is done by manually editing configuration files. To manually edit the files, you need to log in to the virtual machine.

Example public IP block – 192.0.2.0/29

• IP address – 192.0.2.2
• Gateway – 192.0.2.1
• Subnet Mask – 255.255.255.248

Example private IP block – 10.0.0.0/29

• IP address – 10.0.0.2
• Gateway – 10.0.0.1
• Subnet Mask – 255.255.255.248

Public Network

The public network settings are contained in the following file. You need to edit this file with the information that is provided. Replace the example IP addresses with the IP addresses form your public IP block. If the file does not exist, create the file. If it does exist, replace all data that is in the file with the following information:

• /etc/sysconfig/network-scripts/ ifcfg-eth1 DEVICE=eth1 BOOTPROTO=static BROADCAST=192.0.2.7 IPADDR=192.0.2.2 NETMASK=255.255.255.248 NETWORK=192.0.2.0

  GATEWAY=192.0.2.1
  ONBOOT=yes
  

Private Network

The private network settings are in the following file. You need to edit this file with the information that is provided. Replace the example IP addresses with the correct IP addresses from your Private IP block. If the file does not exist, create the file. If the file does exist, replace all data in the file with the following information: Note: The private network WILL NOT have a default route, so the GATEWAY is not defined.

• /etc/sysconfig/network-scripts/ ifcfg-eth0 DEVICE=eth0 BOOTPROTO=static IPADDR=10.0.0.2 NETMASK=255.255.255.248 ONBOOT=yes

Finally, a new route is required to provide private access to the entire private network to include the DNS server, which is done by creating and editing the following file. NOTE: Replace "10.0.0.1" in the example with your private subnet IP gateway.

• /etc/sysconfig/network-scripts/route-eth0 10.0.0.0/8 via 10.0.0.1

DNS Configuration

The primary and secondary DNS configurations are contained in a separate file. You need to edit the file with the following information. If this virtual machine does not have access to the private network, you need to replace the server IPs with the IP addresses of the DNS servers you want to use.

• /etc/resolv.conf nameserver 10.0.80.11 nameserver 10.0.80.12

For these changes to take effect, you need to restart networking on the server. You can restart networking by running the following command:

• service network restart

Ubuntu and Debian

You configure Ubuntu and Debian networks through a single configuration file. You need to edit this configuration file with the following information. To edit this file, you need to have root access to the server. The base installation of Ubuntu does not provide a root login. However, the user that was created in the installation process can access sudo. You need to use the sudo command to edit the file if you are running Ubuntu.

Example public IP block – 192.0.2.0/29

• IP address – 192.0.2.2
• Gateway – 192.0.2.1
• Subnet Mask – 255.255.255.248

Example private IP block – 10.0.0.0/29

·IP address – 10.0.0.2 ·Gateway – 10.0.0.1 ·Subnet Mask – 255.255.255.248

Public and Private Network

Edit the following file with any text editor and replace example IP addresses with the IPs that are in your Public and Private IP blocks.

• /etc/network/interfaces auto lo iface lo inet loopback

  auto eth1
  iface eth1 inet static
  address 192.0.2.2
  netmask 255.255.255.248
  gateway 192.0.2.1
  
  auto eth0
  iface eth0 inet static
  address 10.0.0.2
  netmask 255.255.255.248
  
  #Static route for backend service network
  up route add -net 10.0.0.0/8 gw 10.0.0.1
  

DNS Configuration

The primary and secondary DNS configuration is contained in a separate file. You need to edit this configuration file with the following information. If this virtual machine does not have access to the private network, you need to replace the server IPs with the IP addresses of the DNS servers that you want to use.

• /etc/resolv.conf nameserver 10.0.80.11 nameserver 10.0.80.12

For these changes to take effect, you want to restart networking on the server. You can restart the network by running the following command:

• /etc/init.d/network restart

Note: 192.0.2.0/24 is used as Public IP Documentation per RFC1166 and RFC5737. You do not use these IP addresses on your servers.