By default, each Primary Server that you add to the system is created as a peer to all other Primary Servers. Being in a peer relationship enables a Primary Server to:
Have direct write access to the ZENworks database so that it can add information (inventory, messages, and status).
Retrieve device configuration information directly from the database.
Pull content (bundles, policies, system updates, and patches) from any Primary Server.
Direct write access to the ZENworks database requires a JDBC/ODBC connection. If a Primary Server is located on the network so that it cannot effectively access the ZENworks database via a JDBC/ODBC connection, you can configure the Primary Server to be a child of another Primary Server that does have direct write access to the database. However, you should try to maintain peer relationships between your Primary Servers unless your network connections do not allow it.
Being in a child relationship instructs a Primary Server to use HTTP to roll up inventory, message, and status information to its parent Primary Server, which then writes the information to the database. However, the child Primary Server still retrieves configuration information from the database and passes configuration information back up to the database. For this reason, the child Primary Server must have a direct connection to the ZENworks database.
We do not recommend having a Primary Server across a WAN link from the ZENworks database because this causes increased traffic across the network. We recommend that you use a Satellite device across a WAN link. For more information, see Section 11.2, Satellite Role Relationships.