Chapter 1: Overview

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By using virtualization, it is possible to have a single computer running multiple virtual firewalls, each running a separate software copy. This technique is referred to as virtualization and each virtual firewall can be said to be running in its own virtual machine. This is the basis for the Clavister Virtual Series of products and includes running under VMware™ or the open source KVM virtual environment.

Not only can cOS Stream run in its own virtual machine, the management workstation that is used to administer cOS Stream can also run as a virtual machine on the same or on different hardware. This workstation could be communicating using a CLI console which connects using a Secure Shell (SSH) client.

Supported Virtual Environments

The following virtual environments can host a Clavister Firewall:

The following is required for the virtual CPU:

For a further discussion of resource allocation for all virtual machines, including memory requirements, see Chapter 5, Resource Allocation Guidelines.

Installation Documentation Structure

A general description of installation is given in Chapter 2, Installation. The installation steps in that section are common to all virtual environments. The difference between installation in different virtual environments is the creation and customizing of a virtual machine. This is described in the following parts of this document:


No license is supplied with the default firewall configuration and the only function that is enabled without a license is management access via one of the Ethernet interfaces or the directly connected console. Retrieving and installing a license is described in Chapter 2, Installation as part of the overall installation process.

Referencing Hypervisor Documentation

This guide describes the steps involved when installing and running cOS Stream in a virtualized environment, as well as covering many of the issues that may be encountered when running in such as environment.

The guide tries to deal specifically with the subject of running in the virtual environment and unless relevant, does not go into depth about the hypervisors themselves. The administrator should refer to documentation that is publicly available over the Internet.