Imaging with Ghost
The University of Findlay's College of Education

Multi-Casting

Probably the most important feature of the imaging process for schools is the ability to do multi-casting.

Multi-casting is the distribution of a single image file to multiple clients using only one data stream. In this way, a 1 GB image can be simultaneously sent to many different clients using only 1 GB of total bandwidth. Multi-casting is ideal when rolling out a new set of computers or reconfiguring an entire lab of workstations.

Multi-casting uses one machine to act as a control center server. This machine can be any workstation on the network, or it can actually be the network server. The only requirement is that it be able to run the multi-casting "server" software. This software will determine what image is going to be multi-casted and which machines are going to receive the image.

Create a set of multi-cast boot disks. It will be easier to create the boot disks if you have a DHCP server on your network. Otherwise, unique IP number information will have to be included with each boot disk.

Start the control center server software.

Boot each client machine with one of the boot disks.

Once all the clients are ready to go, initiate the multi-casting process at the control center server. The control center server will keep track of the progress and indicate when the imaging is complete.

Hubs vs Switches

By design, a hub is a party line and lends itself well to multi-casting. A switch is just the opposite; it will try to separate traffic for each computer on the network. Because of this, you may experience problems with imaging using a switch. If you can easily replace a switch with a hub for the imaging process, do so. Otherwise, see if your switch is capable of multi-casting (see your switch documentation), and put your switch in this mode for the duration of your imaging.