DHCP

Context

Dynamic Host Configuration Protocol (DHCP) is used to dynamically manage and configure the IP addresses for users in a centralized manner. DHCP adopts the client/server mode for communication. The client applies to the server for configurations (including IP address, subnet mask, and default gateway), and the server replies with corresponding configuration information based on policies.

Procedure

Global configuration
1. Choose Configuration > Basic Services > DHCP.
2. Set DHCP status to ON in the Global Settings area to enable the DHCP function globally.

Address pool list

Choose Configuration > Basic Services > DHCP.

Click Create in the Address Pool List area. The Create IP Pool page is displayed.

Table 1 describes the parameters on the Create IP Pool page.

**Table 1** Create IP Pool
Parameter	Description
VLANIF interface	Indicates the VLANIF interface name. Select a name from the drop-down list box.
IP/Mask	Indicates the IP address and mask of the VLANIF interface.
DHCP mode	Indicates the DHCP mode. You can select the local allocation or external server allocation mode. In local allocation mode, the device functions as a DHCP server to assign IP addresses to clients. In external server allocation mode, the device functions as a DHCP relay to assign IP addresses to clients through a DHCP server whose address is specified.
Primary DNS server	Indicates the primary DNS server address assigned to a client. This parameter is configured when the DHCP mode is local allocation.
Secondary DNS server	Indicates the secondary DNS server address assigned to a client. This parameter is configured when the DHCP mode is local allocation.
Server IP	Indicates the DHCP server IP address. This parameter is configured when the DHCP mode is external server allocation.

Set the parameters.
Click OK.

Address pool information

Choose Configuration > Basic Services > DHCP.

By clicking an interface address pool (the DHCP mode of the mapping interface is local allocation) in Address Pool Information, you can check the detailed address pool information.

Table 2 describes the parameters on the Address Pool Information page.

**Table 2** Parameters in address pool information
Parameter	Description
Sum of Addresses	Indicates the total number of IP addresses in the address pool.
Allocated	Indicates the number of IP addresses assigned to clients.
Bind IP	Indicates that an IP address in the address pool is bound to a fixed MAC address.
Fix IP	Indicates that an IP address being used or an expired in the address pool is bound to the corresponding MAC address and will be assigned directly to the client when it goes online next time.
Unbind IP	Indicates that a bound IP address is unbound.
Reserve IP	Indicates that an IP address in the address pool is reserved and not assigned.
Release IP	Indicates that a reserved IP address is released and can be assigned.
Reclaim IP	Indicates that an IP address being used or an expired or conflicted IP address in the address pool is reclaimed. The reclaimed IP address becomes idle again and can be re-assigned to clients.
Refresh	Refreshes the page.

Configure IP addresses in the address pool.
1. Select the IP addresses to be configured on the Address Pool Information page.
2. Click Bind IP, Fix IP, Unbind IP, Reserve IP, Release IP, or Reclaim IP.
  
  If you click Bind IP, enter the bound MAC address and click OK.