Multiple Inheritance

A DHCP object can have multiple inherited values and inheritance sources for the DHCP properties. When an object inherits a DHCP property from a source other than the DHCP server, the property value can be the same from all sources or it can be different. When the value is the same, the DHCP server displays the value in the property field. When there are multiple values inherited from multiple paths, the DHCP server displays the information to indicate this is the case.

When two objects serve the same network, the network inherits DHCP properties from both associated objects. If both objects have the same configured DHCP property, the network inherits the same value from both objects. In the same authoritative zone with the two objects serving the same network, the network inherits different values for the same properties if you override the authoritative zone configuration on one object but not on the other.

Multiple Inheritance Criteria

In scenarios where the DHCP configuration uses multiple inheritance, please keep the following criteria in mind:

• Subnets and ranges can have multiple DHCP servers associated with them through assignments.

• When multiple servers are associated with a DHCP configuration and the settings have been saved, a DHCP configuration for that object can only show inheritance for one association at a time. In the Infoblox Portal, it is possible to view each association by selecting it from the Preview Inheritance drop-down menu.

• Only the available, assigned NIOS-X Servers are shown in the Preview Inheritance drop-down menu above the configuration area.

• The table will display the NIOS-X Server in the Preview Inheritance drop-down menu.

• Changes made to inheritable settings apply to objects across all associated DHCP servers.

• The Preview Inheritance drop-down menu is only visible when there is more than one server associated with a DHCP configuration.

Multiple Inheritance Scenario

In a multiple inheritance scenario where multiple External Primary or Internal Secondary NIOS-X Servers possess their own unique profile, the Preview Inheritance drop-down menu will appear above its configuration area. The Preview Inheritance drop-down is only available in scenarios using multiple inheritance. The Preview inheritance drop-down will list the NIOS-X Servers in the order each was added. By selecting a NIOS-X Server from the drop-down list, the display will show from where the selected NIOS-X Server is inheriting its profile.

Using the Preview Inheritance feature, it is possible to view inheritance for all members of a profile. In a scenario having three Internal Secondary NIOS-X Servers (dns NIOS-X Server 1 with an IP address 1.1.1.1, dns NIOS-X Server 2 with an IP address 1.1.1.2, and dns NIOS-X Server 6 with an IP address 1.1.1.6) and an External Primary NIOS-X Server (someNIOS-X Server name.com with an IP address 1.2.3.4), selecting each of the Internal Secondary NIOS-X Servers from the Preview Inheritance drop-down will display the selected Internal Secondary NIOS-X Server’s inheritance profile. The associates for each NIOS-X Server will be listed in the ACCEPT ZONE TRANSFER REQUESTS FROM under the Queries section of the Edit pane. In the case of an External Primary NIOS-X Server, it does not have an inheritance profile associated with it. In a multiple inheritance scenario, objects below the object being overridden become child objects of it, hence they become child objects of the parent object above them, obeying the rules of the hierarchical inheritance chain.