3.7. DHCP

The Dynamic Host Configuration Protocol (DHCP) assigns computers an IP address, a subnet mask, and, as necessary, settings for the gateway or NetBIOS server. The IP address can be static or dynamic.

You can use DHCP to assign and control IP addresses centrally through the LDAP directory. You don’t need to configure each computer manually.

The DHCP integration in Nubus for UCS only supports IPv4.

A DHCP service groups DHCP servers in a shared LDAP configuration. You enter global configuration parameters in the DHCP service and specific parameters in the subordinate objects. For more information, see DHCP services.

You can install a DHCP server from the Univention App Center with the DHCP server application. Alternatively, you can install the univention-dhcp software package. For more information, see Package installation and management in Nubus Manual 1.x [3].

Every DHCP server assigns IP addresses through DHCP. By default, DHCP servers assign only static IP addresses to computer objects registered in the Nubus for UCS LDAP. For more information about DHCP server entries, see DHCP server in Nubus Manual 1.x [3].

If you assign only static IP addresses, you can use as many DHCP servers as required in a DHCP service. All DHCP servers obtain identical data from LDAP, and each server offers the data to DHCP clients. The clients then accept the first response and ignore the rest.

If you also assign dynamic IP addresses, you must use the DHCP failover mechanism and can use a maximum of two DHCP servers per subnet.

A DHCP host entry makes a computer known to the DHCP service. Computers need a DHCP host object to retrieve a fixed IP address through DHCP. You don’t normally need to create DHCP host objects manually, because Nubus creates them automatically when you assign a DHCP service to a computer object with a fixed IP address. For more information about DHCP host entries, see DHCP host in Nubus Manual 1.x [3].

Every subnet requires a DHCP subnet entry, regardless of whether you assign dynamic IP addresses from that subnet. For more information about DHCP subnet entries, see DHCP subnets in Nubus Manual 1.x [3].

You can assign configuration parameters to different IP ranges by creating DHCP pools within subnets. This lets you allow unknown computers in one IP range and exclude them from another. You can create DHCP pools only under DHCP subnet objects. For more information about DHCP pools, see DHCP pools in Nubus Manual 1.x [3].

If several IP subnets use the same physical Ethernet network, create a DHCP shared network object under the DHCP service. Then create a separate DHCP shared subnet object for each subnet under that shared network object. For more information about DHCP shared networks and subnets, see DHCP shared network in Nubus Manual 1.x [3].

Values that you set at a DHCP configuration level apply to that level and all subordinate levels unless you specify other values at those levels. As with policies, the value closest to the object in the configuration hierarchy applies.

See also

DHCP module

in Nubus Manual 1.x [3] for information about how to use the DHCP management module in the Management UI.