The following is a description of how to create custom fields for OSD point and BU, when you pxe boot your client.
How to config Custom Fields Installation
Go in to "OS Deployment, and right click your OSD point and click on "Configuration"
Click on "OSD Gui" and scroll down to the CustomFields"
Here, you have five opportunities, you can choose to your Custom Field.
There is a label shown in you OSDClient, and an default value.
Default Value for "checkbox" can only be TRUE or FALSE
Default Value for "Integer" can only be an number
Default Value for "text" is optinal
Default Value for "ComboBox" is optinal
Now pxe-boot your client, and you will have shown you Custom Fields as shown here: