Before you install the packages (or shortly thereafter), there are some prerequisites that should be satisfied to end up with a fully functioning Eucalyptus system.

 * On each node, configure the system's primary ethernet interface as a bridge. (See the [[http://doc.ubuntu.com/ubuntu/serverguide/C/network-configuration.html#bridging|Ubuntu Server Guide Bridging]] for details).  The node controller will attach virtual network interfaces to this bridge for VM that is started before it to enable network connectivity.  <<BR>> ''Note:'' Remember the name of your node's bridge device (we assume the name of your bridge device is "`br0`" for the rest of this document).  
 * The default Eucalyptus configuration assumes that there is '''not''' a DHCP server in your environment that is handing out dynamic IP addresses.  The Cluster Controller runs a dhcp server that will statically assign IP addresses to VMs (which will be bridged on the local network).
 * From any host that you wish to use as a Eucalyptus client, you should install the `euca2ools` package from universe: {{{
$ sudo apt-get install euca2ools
}}} Also, other tools that can interact with the EC2 and S3 APIs should work with Eucalyptus.
 * If you wish to access Eucalyptus from behind a firewall (i.e. the `euca2ools` tools and the cloud controller will be on different sides of a firewall) then port `8773` ''must'' be open on the cloud controller.  Additionally, if you plan to register your Eucalyptus installation with a cloud management platform, `8773` and `8443` must be open.