9.13. Configuring multiple host-only network interfaces on Solaris hosts

By default VirtualBox provides you with one host-only network interface. Adding more host-only network interfaces on Solaris hosts requires manual configuration. Here's how to add two more host-only network interfaces.

You first need to stop all running VMs and unplumb all existing "vboxnet" interfaces. Execute the following commands as root:

ifconfig vboxnet0 unplumb

Once you make sure all vboxnet interfaces are unplumbed, remove the driver using:

rem_drv vboxnet

then edit the file /platform/i86pc/kernel/drv/vboxnet.conf and add a line for the new interfaces:

name="vboxnet" parent="pseudo" instance=1;
name="vboxnet" parent="pseudo" instance=2;

Add as many of these lines as required and make sure "instance" number is uniquely incremented. Next reload the vboxnet driver using:

add_drv vboxnet

Now plumb all the interfaces using ifconfig vboxnetX plumb (where X can be 0, 1 or 2 in this case) and once plumbed you can then configure the interface like any other network interface.

To make your newly added interfaces' settings persistent across reboots you will need to edit the files /etc/netmasks, and if you are using NWAM /etc/nwam/llp and add the appropriate entries to set the netmask and static IP for each of those interfaces. The VirtualBox installer only updates these configuration files for the one "vboxnet0" interface it creates by default.