Technical data

Configuring the DHCP Server
7.6 Configuring DHCP/BOOTP IP Addressing
If you set the Use MAC addr as Client ID parameter to True, the server uses the
MAC address to uniquely identify the clients. The MAC address field might not
be the actual MAC address of the client’s network adapter. Clients that modify
the structure of the MAC address before sending it to the server include:
• Windows 95, Windows NT, and Windows for Workgroups 3.11 with Microsoft
TCP/IP
On these platforms, the MAC address is prefixed with the hardware type.
The MAC type is 0 and the length is 7 (instead of 6). For example, if your
Ethernet address is 11:22:33:44:55:66, you need to specify the following for
the static IP mapping:
– MAC Address: 01:11:22:33:44:55:66
– MAC Type: 0
– MAC length: 7
• FTP Software’s OnNet client
On this platform, the string "cid-" prefixes the MAC address. The MAC
type is 0 and the length is 16. For example, if your Ethernet address is
11:22:33:44:55:66, you need to specify the following for the static IP mapping:
– MAC Address: cid-112233445566
– MAC Type: 0
– MAC length: 16
7.7 Configuring DHCP Manually
After you run the TCPIP$CONFIG.COM procedure and enable the DHCP server
on your system, you can manually define the following client information on a
case-by-case basis:
• Static, dynamic, or finite addressing
• Other identifying parameters, such as default gateways and DNS domain
names
7.7.1 Tasks Involved
Defining client addressing and additional parameters manually involves the
following steps:
1. Modify the appropriate text-based configuration files.
These files are listed in Section 7.2.2.
You manually edit the DHCP configuration files using a text editor such as
EDT, TPU, or LSE. Depending on your environment, you may or may not
need to modify all the files.
2. If appropriate, run DHCP utilities to update the binary databases.
When you are modifying information already stored in the databases, you use
command line utilities to access and update the database contents. These
utilities are defined as both OpenVMS and UNIX commands. Table 7–10 lists
the utilities.
3. Reinitialize the DHCP server for the changes to take effect (see Section 7.7.3).
7–50 Configuring the DHCP Server