Tag Archives: VMWare

VMWare Virtual Network Lab Setup

Example virtual lab using VMWare. I’ll refer to this as Vlab 1 in case I mention it in latter posts.

The general objective is to set up a small virtual network on which I can build. The virtual machines on the network will access the real network and thus the internet through one of them acting as a gateway.

I’m using 4 headless VMs, all running the Debian based Voyage Linux distro, which is tailored for router applications.

One of these VMs will be bridged to my real LAN, the one simulating an internet gateway. It will perform NAT for the networks behind it on the virtual side.

As an aside, these are running single area OSPF with the Quagga router software but I’ll just talk about the basic interface setup in this post.

Let’s call the 4 Voyage routers alpha, beta, gamma, delta. For what it’s worth, they are all installed in 2GB virtual disks, have one processor core each and 256MB RAM.

Alpha will be the gateway. i.e. the one with a bridged interface to the real network. The 4 VMs are connected in a simple line. Alpha – beta – gamma – delta.

In VMWare’s Virtual Network editor, I’ve configured 3 Vnets for these links. For some reason, it seems you can’t use a /30 subnet for Vnets. Which would be the usual point to point link. Virtual Network Editor just won’t allow it. SO I’m using /29’s.

In my case, Vnets 11, 12, 13.

Vnet 11.
Link between alpha and beta.

Vnet 12.
Link between beta and gamma.

Vnet 13.
Link between gamma and delta.

Alpha has 2 interfaces, one on the real LAN.

And the Host Only Custom link to beta.

The rest are all Host Only Custom links in their respective Vnets.

Beta – alpha:

Beta – gamma:

Gamma – beta:

Gamma – delta:

Delta – gamma:


I have to be organised in how I set these up, more so than perhaps most people. As they’re running headless, no desktop, they have no screenreader running. It may be possible to recompile Voyage with Speakup but that’s beyond me at the moment.

Normally when I’m experimenting with say a single virtual server, I’ll have one interface bridged to my real LAN so I can use my screenreader on the host and SSH in. In this case, I want to force all traffic through the virtual gateway and only have that machine appearing on the LAN. So to reach the others, I need to make sure the routing is setup as I’ll be SSHing to the gateway and hopping from there. As there’s no screenreader on the VMs I can’t just type at the consol.

How I’ve done this is initially set up all VMs with one bridged interface so I can connect and configure the other Host Only connections by editing /etc/network/interfaces. Once I know these are up and reachable from the other VMs, I shut down the bridged interface and comment it out.

As mentioned I am using OSPF and having alpha redistribute the default route that leads out on to the LAN. Were this not the case, I could have used a line in interfaces to set a static default route pointing to the Host Only interface. i.e. through the virtual network towards alpha and the real world.
Post-up route add default gw x.x.x.x

Whilst setting these up it might be worth noting, I did manage to mess up my SSH config file on one of the Vms after I’d already shutdown the bridged interface. Effectively locking myself out due to the no screen reader access on the consol. I fixed it by SSHing into another Voyage VM and counted down how many lines the errant line was. Then did this blind on the misconfigured machine. Cleverer people than I might have used Sed and Grep in some fancy way to fix it…



Voyage Linux

Intro to VMware’s Virtual Networks

I’m using the popular VMware Workstation 10 on Windows Seven. VMware have a number of products. You can download the free VMware Player if you want to run a compatible virtual machine but you can do more with Workstation. Of course there are a number of other virtualisation platforms for Windows, Mac and Linux but I’m with this one.

The Virtual Network Editor that comes with Workstation is where you can set up to 19 virtual networks. Before going on to look at that, note, Under VMware There are 3 types of network connection. NAT, Bridged and Host Only.

NAT. Network Address Translation. The NAT option creates a virtual network behind your host machine on which your guest resides. It has access to the real network resources through your host but doesn’t appear on the network to other devices on your LAN.

Bridged. This takes your virtual machine’s network adapter and bridges it through the host so the guest will appear on the LAN with its own IP address. Either a static one you configure on the guest or if you’re using DHCP, it will get one from your real DHCP server.

Host only. This configuration provides a virtual connection to another virtual machine. So you can have a network of completely isolated VMs if you choose.

Using the Virtual Network Editor, as an example we’ll add a virtual network for host only connection. This will act as a private network between 2 or more guests. The VMware virtual network editor found in the program group in start menu or just use the search, is where you initially set up virtual networks or Vnets. Some of these Vnets are configured by default. Vnet 0 provides the bridged connection. Vnet 8, is for NAT. Of this latter type, you can have only one anyway.

To add a custom Vnet click add. Choose the Vnet you want to use. You can think of these like virtual switches. When configuring guest’s network interfaces, you effectively connect them to these virtual switches.

Choose Host Only.

To have this network only be available to your guests, not your host. Untick Connect a Host Virtual Adapter to This Network.

VMware has its own DHCP server for these Vnets. In my case I untick this box as I want to either configure static addresses or set up a DHCP server on one of the guests themselves.

Next choose the IP and subnet you want for this network. Click OK, you’re done.

Now from within VMware, VM Menu, Settings, you can add or change the network adapter settings for the selected guest. For example from the Hardware tab, go to add and choose Network Adapter.

Choose the Host Only setting Click OK.

Highlight this new interface in the list view and select the Custom radio button. You can now choose the Vnet you configured earlier to which this virtual network interface will be connected.

Later I’ll give an overview of how I set up a small virtual network lab using these custom networks, with a guest acting as a router, linking them to my real network and thus internet access.

Virtual Vinux Revisitted

Last year I tried running the virtual Vinux distribution under Windows XP Home SP3. Whilst it worked with no major problems and was easy to set up, orca’s speech was rather crackly. This made it in the end, pretty difficult to use for any length of time. Role on several months, I’m now using Windows Seven Professional and decided to try it again.

I downloaded Vinux virtual from the Vinux project website.

It might be worth noting, the virtual edition is 3.02. This is based on Ubuntu 10.4 LTS. The standard release of Vinux is now at version 4.0, based on Ubuntu 12.04.2 LTS.

The download includes instructions for running Vinux, some batch files for assisting in the customisation and the free VMWare Player. The VMWare Player allows users to host virtual machines on their desktop. VMWare recommend at least 1GB of RAM and a 2.0 GHZ processor to host a virtual machine successfully. For the record, I’m running it on a 2.4 GHZ Intel Quadcore q6600 system with 4 GB of RAM. The host operating system is Windows Seven Professional. VMWare products are also available for Linux and mac.

In practise.

After following the installation instructions, which guide you through adding the Vinux virtual machine to VMWare Player and offer some quick start tips, you should now have an accessible version of Linux comfortably hosted within Windows. I used the default settings, giving the VM 512MB of RAM and 80GB of disk space. It performs very well although I’ve not done anything taxing with it yet. You can of course add software as you normally might within Debian derived Linux’, with apt-get for example. Switching between the VM and Windows is done through a simple keyboard short cut when the VMWare Player has focus. Various settings for the VM can be edited in a regular text editor using the .vmx file in the download.

Next I intend to install the Virtual Network Editor, which is part of the VMWare Player software although not installed automatically. The purpose being, so I can access the Vinux machine from other hosts on the network.