How to set up split-scopes.
- The same DHCP scope is deployed to both servers.
- Each server receives a separate address pool based on the split point, as described in the Example1 in Windows DHCP Split-Scopes in Address Manager.
If the network contains any DHCP reserved addresses, the reservations are deployed to both servers. However, because the reservation falls outside the range on one server, the range on that server expands to accommodate the DHCP reservation. Any IP addresses that lie between the reservation and the start of the range are excluded. This is discussed in greater detail in Windows DHCP Reservations.
To set up split-scopes:
- Navigate to an IPv4 network and select the Deployment Roles tab.
- Click New, then select DHCP Role. The Add DHCP Role page opens.
- Under Role, select Master from the Type drop-down menu.
Under Server, click Select Server
Interface. The Select Server Interface page
opens. Select a Windows server and click Add.
Note: When you add a server, a Failover Config section appears on the Add DHCP Role page.
- Click Select Secondary Server Interface. The Select Server Interface page opens.
Select another Windows server, then click Add.
Note: Scope-splitting requires that two servers be specified on the Add DHCP Role page. If a second server is not specified, a warning appears during deployment indicating that a second server is required.
- On the Add DHCP Role page, click Add.
- Select the DHCP Ranges tab.
- Click New. The Add IP4 Network DHCP Range page opens.
- Under Address Range, type the start and end IP addresses for the DHCP range in the Start and End fields. In the Name field, enter a name to describe the range.
Under Scope (Range) Split, select Scope Split
Windows Network. A set of options and fields appears in the
Scope (Range) Split section. Set the following
- Exclude Server 1—excludes the entire DHCP range from Server 1. The entire range is active for Server 2.
- Exclude Server 2—excludes the entire DHCP range from Server 2. The entire range is active for Server 1.
- Split Address—type an IP address at which to divide the range. The range is divided between the servers with the split address assigned to the active range on the first server.
Click Preview to show the active and excluded ranges for
Server 1 and Server 2.
As an example, you could have a DHCP range between 10.0.0.10 and 10.0.0.200 split at 10.0.0.100, with the split address 10.0.0.100 assigned to the Active range on Server 1.
- Click Add. The DHCP range appears on the DHCP Ranges tab.
On the DHCP Ranges tab, click the range you just
defined. The Details page for the range opens.
- To edit the name and DHCP alert settings for the range, click Edit.
- To edit the address range and scope-splitting settings, click
Note: To clearly identify DHCP ranges that use scope-splitting, set the DHCP ranges table to display the Scope Split Address column.