[[!summary chatGPT: The author describes their setup for experimenting with deployment by installing virtual Linux distributions using Virtualbox, solving networking issues and enabling internet access for all hosts using masquerading and configuring a DHCP server.]]
[[!meta date="2010-12-21 03:16"]]
[[!tag gentoo packagemanager]]

to **experiment with deployment** i've installed several linux distributions using **virtualbox** (based on iso images). i had some problems with the networking but today i got rid of the complicated setup, used previously.

# what i want
    
    |-------------------------------------------|
    |       fedora      debian       windows    |
    |  10.0.0.100    10.0.0.101   10.0.0.102    |
    |          |          |          |          |
    |          --------|||||||-------|          |
    |                     | switch              |
    |---------------------|---------------------|
                          |
                          | vboxnet0 10.0.0.1/24


virtualbox adds the **vboxnet0** (**host only network adapter**) using the preferences dialog in the main gui. additionally i added masquerading, using a external script, in order to have all hosts inside the 'host only networking' accessing the internet. the switch is created by virtualbox automatically when selecting 'host only networking' using **vboxnet0** per **appliance**.

i was using '=app-emulation/virtualbox-ose-3.2.10'.


# how to do it


the setup is quite easy, i just wanted to write it down anyway in case it is of help for others.


# masquerading


in order to get each **virtualbox appliance connected with the internet**, masquerading is used. this is basically a one way internet connection but in my scenario there are no services provided to the outside world.


    iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE
    echo 1 > /proc/sys/net/ipv4/ip_forward

# dhcp server

**as the virtualbox-built-in dhcp server did not work at all**, i decided to use =**net-misc/dhcp-3.1.2-p1** instead. so here is the configuration:

    
    dhcp.conf
    # option definitions common to all supported networks...
    option domain-name "example.org";
    option domain-name-servers 10.0.0.1;
    
    default-lease-time 600;
    max-lease-time 7200;
    ddns-update-style ad-hoc;
    
    log-facility local7;
    
    subnet 10.0.0.0 netmask 255.255.255.0 {
      option domain-name-servers 8.8.8.8;
      range 10.0.0.10 10.0.0.200;
      option routers 10.0.0.1;
    }
    
    subnet 192.168.56.0 netmask 255.255.255.0 {
      option domain-name-servers 8.8.8.8;
      range 192.168.56.101 192.168.56.202;
      option routers 192.168.56.1;
    }


i run this server from a script which is also started at boot time:

    dhcp eth0 vboxnet0

this is helpful as i can configure static IPs for known mac addresses. but also automatic assignment should be quite stable as all parameters can be tuned as used to.

# the clients

as mentioned already, each **client** has to be **assinged** to the '**host only network' adapter**: **vboxnet0**. most linux distributions will try to get the host address via dhcp automatically. also each host can communicated with each other, so it is easy to do maintainance stuff.

**update: 2010-12-21** modified article as it's not clear why some things are done the way they are