Configuring DHCP Server for Dynamic Ranges

Because SonicOS allows multiple DHCP scopes per interface, there is no requirement that the subnet range is attached to the interface when configuring DHCP scopes.

To configure DHCP server for dynamic IP address ranges:
1
In the Network > DHCP Server page, at the bottom of the DHCP Server Lease Scopes table, click Add Dynamic. The Dynamic Ranges Configuration dialog is displayed.

General Settings
2
In the General page, make sure the Enable this DHCP Scope checkbox is selected if you want to enable this range.
3
To populate the Range Start, Range End, Default Gateway, and Subnet Mask fields with default values for a certain interface, select the Interface Pre-Populate checkbox near the bottom of the page and choose the interface from the drop-down menu. The populated IP addresses are in the same private subnet as the selected interface.
* 
IMPORTANT: To select an interface from the Interface menu, it must first be fully configured and it must be of the zone type, LAN, WLAN, or DMZ, or be a VLAN sub-interface.
4
Use the populated IP address range entries in the Range Start and Range End fields or type in your own IP address range.
5
Type the number of minutes an IP address is used before it is issued another IP address in the Lease Time (minutes) field. 1440 minutes (24 hours) is the default value.
6
Use the populated gateway address or type the IP address of the gateway into the Default Gateway field.
7
Use the populated subnet mask or type the gateway subnet mask into the Subnet Mask field.
8
Select Allow BOOTP Clients to use Range if you have BOOTP Clients on your network.

BOOTP stands for bootstrap protocol, which is a TCP/IP protocol and service that allows diskless workstations to obtain their IP address, other TCP/IP configuration information, and their boot image file from a BOOTP server.

DNS/WINS Settings
9
Click the DNS/WINS tab to continue configuring the DHCP Server feature.

10
If you have a domain name for the DNS server, type it in the Domain Name field.
11
Inherit DNS Settings Dynamically using SonicWALL’s DNS Settings automatically populates the DNS and WINS settings with the settings in the Network > DNS page. This option is selected by default.
12
If you do not want to use the firewall’s network settings, select Specify Manually, and type the IP address of your DNS Server in the DNS Server 1 field. You can specify two additional DNS servers.
13
If you have WINS running on your network, type the WINS server IP address(es) in the WINS Server 1 field. You can add an additional WINS server.
Advanced Settings
14
Click on the Advanced tab. The Advanced tab allows you to configure DHCP server to send Cisco Call Manager information to VoIP clients on the network.

15
Under VoIP Call Managers, enter the IP address or FQDN of your VoIP Call Manager in the Call Manager 1 field. You can add two additional VoIP Call Manager addresses.
16
Under Network Boot Settings, in the Next Server field, enter the IP address of the PXE boot server (TFTP server) that a PXE client uses during the next stage of the boot process.

The fields under Network Boot Settings are used in a Pre-boot Execution Environment (PXE), in which the client boots up using files obtained over a network interface. The PXE client obtains the IP address and name of the PXE boot server, and the boot file name, from the DHCP server.

When using these options, select PXE under DHCP Generic Options.

17
In the Boot File field, type in the name of the boot file that the PXE client can get over TFTP from the PXE boot server.
18
In the Server Name field, type in the DNS host name of the PXE boot server (TFTP server).
19
For information on configuring DHCP Generic Options see Configuring DHCP Generic Options for DHCP Lease Scopes .
20
Click OK.
21
Click Accept for the settings to take effect on the firewall.

For more information on VoIP support features on the Dell SonicWALL Security Appliance, see VoIP Overview .