Depending on which dialog box you accessed, you can either add a new Multicast Image Set action to the current bundle’s Preboot actions, or edit an existing Multicast Image Set.
Multicast Image Set bundles use an image that was previously taken from a device and stored on an Imaging Server. The image is sent to multiple devices at one time to reimage them, rather than being sent one time for each device, thus saving on network bandwidth usage. For example, if you have 10 devices in the multicast session and the image is 3 GB in size, your network experiences 3 GB of network traffic to image all 10 devices. Without multicasting, the network experiences 30 GB of network traffic.
For multicasting to work properly, all routers and switches on the network must have their multicast features configured. Otherwise, multicast packets might not be routed properly.
A multicast session consists of all clients (devices) that are assigned to the Multicast Session Set bundle that are booting (joining), but must wait for a start trigger in order to complete booting. In other words, the boot processes for the devices can be held up until one of the triggers is encountered. You specify an elapsed time or number of clients entry as the trigger.
After a session has started, other devices that boot and that are assigned to this bundle do not become part of this session, but become part of the next session when it triggers.
There are two triggers (elapsed time or number of clients joining) that you can use to determine when to start the multicast session. The first trigger to be encountered starts the session. These triggers are useful if you want economy of scale in having multiple clients join, but you don’t want to stall the session too long.
Specify a multicast name in the Action Name field.
Specify the minimum number of clients needed in order to start the multicast session.
Specify the time to wait before starting a multicast session if not enough clients have connected. The time out period is reset after each client joins the session. For example, if you have set 5 minutes as the time out period, and if client 2 joins the session at third minute, then the time out is calculated afresh from the time the client 2 joins the session.
In the Items to be Included in the Multicast Session field, do the following as applicable:
To add an image, click Add Image, then browse for and select the image file.
To add an application, click Add Application, then browse for and select the application file.
To edit an existing entry, select the entry, then click Edit.
Use the Move Up and Move Down buttons to change the order of execution for the listed items.
To remove an entry, select it, then click Remove. You can select and remove multiple items at a time.
Click OK to create the new multicast action.
In the Action Name field, edit the existing name as needed.
If necessary, change the number of clients needed in order to start the multicast session.
If necessary, change the time to wait before starting a multicast session if not enough clients have connected.
As necessary, edit the Items to be Included in the Multicast Session field.
You can add or remove items, edit existing items, or change their order of execution.
Click OK to save the changes.